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Former White House Coordinator for Arms Control and WMD Terrorism
Chemical/Biological Arms Control

The U.S. Cold War-Era Chemical Weapons Stockpile

Contact: Leanne Quinn, Chemical Weapons Convention Coalition Program Assistant, (202) 463-8270 x106

In 1990, on the heels of the Cold War, the United States possessed the world's second largest chemical weapons arsenal after Russia, consisting of more than 31,500 U.S. tons (28,577 MT) of lethal chemical agents and munitions.

Following years of bilateral talks with Russia and multilateral negotiations in the Conference on Disarmament in Geneva on chemical weapons disarmament, the United States decided in 1986 to take unilateral action to begin the destruction of its chemical weapons stockpile. The demilitarization effort was prompted by Congressional legislation (Public Law 99-145) calling for the safe destruction of the United States’ stockpile of nonbinary lethal chemical agents and related facilities.

Since transport of chemical weapons was highly contentious - and was later outright banned by Congress in 1994 (50 U.S. Code 1512a) -  the U.S. Army's chemical weapons destruction plan relied on destruction facilities located at the nine U.S. chemical weapons depots in Anniston, Alabama; Pine Bluff, Arkansas; Pueblo, Colorado; Newport, Indiana; Richmond, Kentucky; Edgewood, Maryland; Umatilla, Oregon; Tooele, Utah; and Johnston Atoll. Dustruction efforts began at the first destruction facility, Johnston Atoll, in 1990.  

By 1997, when the Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and on Their Destruction (also known as the Chemical Weapons Convention or the CWC) entered into force, the United States had destroyed only 1,434 MTs of its chemical agents and munitions. As a member state of the CWC, the United States committed to the destruction of its remaining chemical weapons inventory.

The chart below summarizes the types and quanties of chemical weapons that were once in the U.S. chemical weapons stockpile, including the agents and munitions that have already been destroyed. To date, all chemical agents and munitions stored at Aberdeen, Anniston, Johnston Atoll, Newport, Pine Bluff, and Tooele have been eliminated; the Pueblo (Colorado) and Blue Grass (Kentucky) destruction facilities are still operational.

The data are drawn from the records published by the Program Manager for Chemical Demilitarization and the U.S. Army Chemical Materials Agency in 1996, 2000, 2011, and 2012.

As of April 15 2022, there are 646.7 U.S. tons of chemical agents and munitions left to be destroyed. Official updates on the effort to complete the destruction process at the Pueblo and Blue Grass destruction facilities are available online here.

Under the provisions of the CWC, the United States must finish destroying its remaining chemical weapons by Sept. 30, 2023.

Agent Type Key:

GA – nerve agent, also known as Tabun
GB – nerve agent, also known as Sarin
HD – blister agent, sulfur mustard (nearly pure)
H – blister agent, sulfur mustard (20%-30% impurities
HT – blister agent, sulfur mustard (60% HD and 40% agent T)
Lewisite – blister agent, the central atom is arsenic
VX – nerve agent

Quantity and Type of Former U.S. Chemical Agents and Munitions by Stockpile Location

Storage Site Agent Type Munitions Quantity
(number of munitions)
Start Date
End Date
Aberdeen Proving Ground, Maryland HD ton containers 1,818 Apr 23, 2003 Feb 2006
Anniston Army Depot, Alabama HT 4.2-inch cartridges 183,552 Aug 9, 2003 Sep 22, 2011
HD 4.2-inch cartridges 75,360
HD 105mm cartridges 23,064
HD 155mm projectiles 17,643
HD ton containers 108
GB 105mm cartridges 74,014
GB 105mm projectiles 26
GB 155mm projectiles 9,600
GB 8-inch projectiles 16,026
GB M55 rockets 44,738
GB M56 rocket warheads 260
VX 155mm projectiles 139,581
VX mines 44,131
VX M55 rockets 35,662
Blue Grass Army Depot, Kentucky HD 155mm projectiles 15,492 Jun 7, 2019 Sept 30, 2023
GB 8-inch projectiles 3,977
GB M55 rockets 51,740
VX 155mm projectiles 12,816
VX M55 rockets 17,739
Johnston Atoll HD 155mm projectiles 5,779 Jun 30, 1990 Nov 29, 2000
HD 105mm projectiles 46
HD M60 projectiles 45,108
HD 4.2-inch mortars 43,600
HD ton containers 68
GB M55 rockets 58,353
GB 155mm projectiles 107,197
GB 105mm projectiles 49,360
GB 8-inch projectiles 13,020
GB MC-1 bombs 3,047
GB MK 94 bombs 2,570
GB ton containers 66
VX M55 rockets 13,889
VX 155mm projectiles 42,682
VX 8-inch projectiles 14,519
VX land mines 13,302
VX ton containers 66
Newport Chemical Depot, Indiana VX ton containers 1,690 May 5, 2005 Aug 8, 2008
Pine Bluff Arsenal, Arkansas HT ton containers 3,591 Mar 28, 2005 Nov 12, 2010
HD ton containers 107
GB M55 rockets 90,231
GB M56 rocket warheads 178
VX M55 rockets 19,582
VX M56 rocket warheads 26
VX mines 9,378
Pueblo Army Depot, Colorado HT 4.2-inch cartridges 20,384 Sep 7, 2016 Sept 30, 2023
HD 4.2-inch cartridges 76,722
HD 105mm cartridges 383,418
HD 155mm projectiles 299,554
Tooele Army Depot, Utah H 155mm projectiles 54,663 Aug 22, 1996 Jan 21, 2012
HT 4.2-inch cartridges 62,590
HD 4.2-inch mortar 976
HD ton container 6,398
GB 105mm projectiles 798,703
GB ton containers 5,709
GB MC-1 bombs 4,463
GB M55 rockets 28,945
GB M56 rocket warheads 1,056
GB 155 mm projectiles 89,142
GB Weteye bomb 888
VX M55 rockets 3,966
VX M56 rocket warheads 3,560
VX ton containers 640
VX 155mm projectiles 53,216
VX 8-inch projectiles 1
VX spray tanks 862
VX landmines 22,690
GA ton containers 4
Lewisite ton containers 10
Umatilla Depot Activity, Oregon H ton containers 2,635 Sep 7, 2004 Oct 25, 2011
GB 155mm projectiles 47,406
GB 8-inch projectiles 14,246
GB M55 rockets 91,442
GB 500-lb bombs 27
GB 750-lb bombs 2,418
VX 155mm projectiles 32,313
VX 8-inch projectiles 3,752
VX mines 11,685
VX M55 rockets 14,519
VX spray tanks 156

The data on this chart was sourced from the archived websites of the Program Manager for Chemical Demilitarization (June 24, 1997, Oct. 1, 2000) and the U.S. Army Chemical Materials Agency (Sept. 22, 2011; Feb. 6, 2012).

Chemical/Biological Arms Control

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Timeline of Chemical and Biological Weapons Developments During Russia's 2022 Invasion of Ukraine

Contact: Leanne Quinn, Program Assistant for the Chemical Weapons Convention Coalition

Following Russia’s invasion of Ukraine on February 24, 2022, there have been a number of accusations and concerns regarding chemical and biological weapons. The following is a chronological summary of key events and quotes related to chemical and biological weapons developments during the conflict. The timeline will be updated as necessary. 


December 21: Russian defense minister, Sergei Shoigu, alleged that American military contractors are secretly smuggling “tanks filled with unidentified chemical components” into Ukraine “for the purpose of carrying out acts of provocation.” 


February 17: U.S. Secretary of State Antony Blinken went before the U.N. Security Council to warn that Russia could stage a “false flag” incident as a pretext for an invasion, including a chemical weapons attack.

February 27: Ukraine submitted Note Verbal No. 61219/30-196/50-3 to the OPCW, raising the concern that Russian armed forces might be preparing a “false flag” incident using chemicals, such as the explosion of industrial tanks filled with chemicals (Ukraine: 27 February 2022 – 61219/30-196/50-3). 

March 8: During the 99th Executive Council session of the Organization for the Prohibition of Chemical Weapons (OPCW), the Ukrainian delegation condemned Russian misinformation and re-affirmed Ukraine’s compliance with and support for the Chemical Weapons Convention. Ukrainian Amb. Maksym Kononenko made it clear that, should a chemical incident occur in Ukraine, Ukraine will invoke Article X of the Chemical Weapons Convention, which calls for the delivery of “Assistance and Protection Against Chemical Weapons” by other States Parties to the CWC.  

Forty-nine nations submitted a joint statement to the OPCW condemning Russia’s disinformation campaign, particularly Russian Defense Minister Shoigu’s December 21 statements (see Dec. 21 in timeline). 

March 9: Russian foreign ministry spokesperson Maria Zakharova said that Russia “has documents showing evidence that the US had supported a bioweapons program in Ukraine,” and that “Ukrainian nationalists” were preparing a chemical weapons “provocation” (The Guardian). The State Department and White House categorically denied the claims. 

March 9: White House spokeswoman Jen Psaki warned that Russia could “possibly use chemical or biological weapons in Ukraine, or to create a false flag operation using them.” 

March 10: Russia submitted a “non-paper” to the U.N. Security Council “on several scenarios of false-flag chemical provocations by Ukrainians” and alleged that the U.S. and private military companies are assisting Ukraine in this effort. 

March 10: Russia submitted a National Document to the OPCW entitled “About the possible chemical provocations in Ukraine” repeating its claim that American “special services” have provided Ukraine chemicals for “various types of provocations” (Russian Federation: 10 March 2022 – NV_5). The document outlined several possible ways a chemical attack could take place. 

March 10: Appearing before a Senate Intelligence Committee hearing on worldwide threats to the U.S., CIA Director William Burns stated: “Whether it’s the potential for the use of chemical weapons either as a false flag operation or against the Ukrainians, this is something that all of you know is very much a part of Russia’s playbook. They’ve used those weapons against their own citizens, they’ve at least encouraged their use in Syria and elsewhere, so it’s something we take very seriously.”

March 11: The Russian Mission to the U.N. called for a U.N. Security Council meeting to discuss its accusations that the United States is funding a network of military biological laboratories. The United States Delegate, Amb. Linda Thomas-Greenfield, responded: “There are no Ukrainian biological weapons laboratories supported by the United States – not near Russia’s border or anywhere.” U.N. High Representative for Disarmament Affairs, Izumi Nakamitsu, dismissed the claims, saying “the United Nations is not aware of a biological weapons program” in Ukraine.

March 11: Biden warned that “Russia would pay a severe price if they use chemical weapons.” 

March 16: U.S. National Security Advisor Jake Sullivan spoke with General Nikolay Patrushev, Secretary of the Russian Security Council, over the phone. Mr. Sullivan warned “about the consequences and implications of any possible Russian decision to use chemical or biological weapons in Ukraine.” 

March 18: The Russian Mission to the U.N. called for a second U.N. Security Council meeting to discuss its accusations that the United States is funding a network of military biological laboratories. U.N. High Representative for Disarmament Affairs Izumi Nakamitsu once again stated that the U.N. “is not aware of any such biological weapons programs,” and further stated that “the United Nations currently has neither the mandate nor the technical or operational capacity to investigate this information.” 

March 18: Ukraine submitted a request to the OPCW for “bilateral assistance from States Parties in order to protect against chemical weapons,” invoking Article X of the Chemical Weapons Convention. The letter specifically requested: assistance and detection equipment and alarm systems; protective equipment; decontamination equipment and decontaminants; medical antidotes and treatments; and advice on any of these protective measures. Ukraine also stated concern that the “Russian Federation is going to launch a massive chemical attack on the territory of Ukraine, in the capital of Ukraine city of Kyiv and Kyiv region as well as in temporarily occupied Donetsk using tanks with ammonia and central nervous system acting chemicals.” 

March 21: An ammonia leak occurred at a Sumykhimprom chemical facility in Sumy, Ukraine. The factory produces fertilizers. The Associated Press first reported on the 21st that the cause of the leak was unknown. Sumy regional governor, Dmytro Zhvytsky said that the leak was caused by Russian shelling. Russia has accused Ukraine of staging a “chemical false flag.” 

March 22: Speaking on the condition of anonymity, a senior U.S. defense official commented that the U.S. is closely monitoring intelligence for indications of a Russian chemical or biological weapons attack in Ukraine. He further stated: “There’s no indication that there’s something imminent in that regard right now” (Reuters).

March 21: Speaking at a Business Roundtable, U.S. President Joe Biden stated that Putin’s “back is against the wall. And he’s – now he’s talking about new false flags he’s setting up, including he’s asserting that, we, in America, have biological as well as chemical weapons in Europe – simply not true. I guarantee you.” He followed this statement with: “They’re also suggesting that Ukraine has biological and chemical weapons in Ukraine. That’s a clear sign he is considering using both of those. He’s already used chemical weapons in the past.” 

March 21: In an effort to “demonstrate its commitment to cooperation and transparency,” the United States held a virtual “U.S. Chemical Demilitarization Transparency Event” for OPCW regional officials. Led by Under Secretary of State for Arms Control and International Security Bonnie Jenkins, the event “highlighted the progress the U.S. has made in destroying the last of the chemical weapons stockpile” and re-affirmed that the U.S. will finish destroying the final 3% of its stockpile by September 2023. 

March 24: In a joint statement, NATO countries promised to “continue to provide assistance in such areas as cybersecurity and protection against threats of a chemical, biological, radiological, and nuclear nature” during a meeting of the NATO Heads of State and Government. The statement also warned that “Any use by Russia of a chemical or biological weapons would be unacceptable and result in severe consequences.” 

March 24: While at the NATO summit in Brussels, U.S. President Joe Biden said that if Russia uses chemical weapons, “We would respond.” He added, “The nature of the response would depend on the nature of the use.” 

April 1: White House press secretary Jen Psaki confirmed that the United States “is providing the government of Ukraine with lifesaving equipment and supplies that could be deployed in the event of Russian use of a chemical or biological weapons against Ukraine.”

April 4: A reporter asked U.S. White House press secretary Jen Psaki about the delivery status of the equipment described during the April 1 press briefing (see above). Psaki replied that U.S. government was trying to deliver the equipment in an “expedited manner” and that she would do a status check to see if the “equipment has been delivered, or is in process.” 

April 4: U.S. announced it has allocated $250,000 of its voluntary OPCW contribution to the OPCW Trust Fund for Implementation of Article X. The money is earmarked for “the provision of assistance and protection to Ukraine in the event of the use or threat of use of chemical weapons.” 

April 4-11: The second session of the Preparatory Committee for the Ninth Review Conference for the Biological Weapons Convention convened in Geneva to prepare for the upcoming Conference, which is scheduled to take place 28 November - 16 December 2022. Russia distributed a note verbale to BWC states regarding its allegations of US-funded facilities in Ukraine. While the document is not yet publicly available, the allegations mentioned in the document were reportedly similar to the allegations expressed by Russia during the March UN meetings (see: March 11, March 18).

April 7: The G7 foreign ministers and the high representative of the European Union issued a joint statement "On Russia's War of Aggression Against Ukraine." The statement included the following: "We warn against any threat or use of chemical, biological or nuclear weapons. We recall Russia’s obligations under international treaties of which it is a party, and which protect us all. Any use by Russia of such a weapon would be unacceptable and result in severe consequences. We condemn Russia’s unsubstantiated claims and false allegations against Ukraine, a respected member of the Biological and Toxin Weapons Convention and the Chemical Weapons Convention that is in compliance with its legal obligations under those instruments."

April 8: The humanitarian organization DirectRelief confirmed that it had delivered 220,000 vials of atropine, a drug which can mitigate the effects of sarin and other chemical agents, to Ukraine.

April 11: A message was posted on Telegram by the Azov Regiment, an "ultra-nationalist part of the Ukrainian National Guard," alleging that Russian forces had used "a poisonous substance of unkown origin." (Source: CNBC) There has been no official statement from any government body confirming that a chemical attack took place. British Foreign Secretary Liz Truss said on Twitter that the UK is urgently working to verify details of the incident. This story will be updated as more details emerge. 

April 19: Japan’s defense minister, Nobuo Kishi, announced that Japan was sending “anti-chemical-warfare equipment” to Ukraine, including gas masks, hazmat suits, and drones.

April 20: White House spokesperson Jen Psaki was asked for an update on U.S. assessments of the alleged chemical incident in Mariupol (see April 11). Psaki replied that "there's no new assessment." She added that because the U.S. doesn't have a team on the ground, the situation is "difficult to assess," but that the U.S. will continue to work on investigating the incident. 

April 23: According to Russian news agency Tass, Russian military officials are warning that the U.S. could conduct a false-flag "provocation" in order to accuse Moscow of using a weapon of mass destruction (chemical, biological, or nuclear weapon). 

April 26: During a press conference at the Rossiya Segodnya information agency, Russian Permanent Representative to the Organization for the Prohibition of Chemical Weapons Alexander Shulgin stated: "When Ukraine joined the chemical convention, it did not declare the presence of chemical weapons on its territory, but I think that, one way or another, the Ukrainians will play this card. I already spoke about encroachments regarding chemical provocations against our country."  

April 29: In a statement marking the 25th anniversary of the entry into force of the Chemical Weapons Convention, U.S. Secretary of State Antony Blinken said, "We will also continue our efforts to hold the Kremlin accountable for its noncompliance with the CWC, repeated use of chemical weapons, and ongoing efforts to shield the Assad regime from accountability for its CW use.  Further, we have made very clear that the Russian government would face profound consequences were it to use chemical weapons in Ukraine."

May 13: Russia called a third UN Security Council meeting to discuss its allegations that the United States is carrying out dangerous biological projects in Ukraine-based laboratories.

UN Disarmament Director and Deputy High Representative Thomas Markham briefed the UN Security Council and stated, "I wish to note that Under-Secretary-General Nakamitsu informed the Council in her respective briefings on 11 and 18 March 2022, that the United Nations was not aware of any biological weapons programmes in Ukraine. This remains the case." Markham advised any nation that still has compliance concerns to use procedures available under the Biological Weapons Convention to settle those concerns. 

May 16: Sergei Ryabkov, the Deputy Minister of Foreign Affairs of Russia, announced that Russia is planning to "move forward with the launching of the official investigation by the UN Security Council" into allegations about biological laboratory activities in Ukraine. 

May 18: Russia submitted a note to the OPCW accusing Ukrainian Security Services of carrying out “the explosive destruction of a pre-planted high-explosive round that was amplified with an overlay of up to one tonne of ammonium nitrate” on May 16 in Mazanovka (see Russian Federation: 18 May 2022 – NV_19 of OPCW document). The note went on to say that the explosion caused the formation of a toxic cloud that moved towards the town of Kramatorsk, and alleged that the goal of this incident was to “accuse the Russian army of using chemical weapons.” 

May 30: Russia submitted another note to the OPCW alleging that, according to information gathered from Ukrainian prisoners of war, Ukrainian nationalists are planning “another provocation involving toxic substances” (see Russian Federation: 30 May 2022 – NV_23 of OPCW document). 

May 30: Ukraine submitted a letter to the OPCW alleging that on May 30, Russian troops shelled an ammonia pipeline “Togliatti – Odesa” in the Bakhmut district, Donetsk region. The letter also claimed that, as a result of the alleged shelling, there was an ammonia leak which caused a toxic cloud that moved over several nearby villages. There were no casualties reported. (See Ukraine: 30 May 2022 – NV_61219/35-196/50-36735 of OPCW document). 

May 31: Russia refuted Ukrainian claims that Russian shelling struck an ammonia pipeline at the Odessa Port Plant in a letter to the OPCW (see Russian Federation: 31 May 2022 – NV_25 of OPCW document). 

May 31: In a note to the OPCW, Ukraine alleged that “on the 31 of May at 06:45 pm the Russian military targeted the large-scale chemical industry complex ‘Azot’ in order to create chemical pollution” (see Ukraine: 31 May 2022 – NV_51219/35-196/50-37431 of OPCW document). The letter also alleged that a railway tank containing nitric acid was damaged, causing the release of a cloud of toxic chemicals. No casualties were reported. 

June 1: The British Embassy in the Netherlands submitted a note to the OPCW condemning Russia’s allegations about chemical weapons provocations being prepared in Ukraine (see United Kingdom: 1 June 2022 – NV_63/2022 of OPCW document). 

June 1: Responding to the Ukrainian allegations regarding the chemical industry complex “Azot” (see May 31), Russia submitted a letter to the OPCW claiming that, “as early as on 6 May 2022, the Ministry of Defence of the Russian Federation warned about the provocation at the ‘Azot’ plant in the city of Severodonetsk, in the People’s Republic of Lugansk, being prepared by Ukrainian nationalists planting bombs on containers holding hazardous chemicals” (see Russian Federation: 1 June 2022 – NV_26 of OPCW document). 

June 6: Russia submitted a note to the OPCW alleging that, “the Kiev authorities, having recognised that it is not possible to continue to resist and hold the industrial zone in the city of Severodonetsk, in the People’s Republic of Lugansk, have instructed a composite task group (the surviving contingent of 2 the 79th detached air assault brigade of the Ukrainian Armed Forces, the 117th and 118th detached battalions, and the 111th detached territorial defence brigade) to plant explosives on containers of the Severodonetsk enterprise “Azot” holding nitrate and nitric acid, the total amount of which exceeds 100 tonnes” (see Russian Federation: 6 June 2022 – NV_27 in OPCW document). 

June 9: Russia submitted another note to the OPCW accusing Ukraine of preparing a chemical false flag incident (see Russian Federation: 9 June 2022 – NV-29 of OPCW document). Russia went on to allege that, should a provocation take place, the OPCW will use the provocation to accuse Russia of using chemical weapons. 

June 10: The OPCW responded to Russia’s accusations (see June 9) by stating the Technical Secretariat for the OPCW “works impartially for the 193 States Parties to the Convention” and that the Secretariat is “composed of international civil servants who originate from more than 80 countries from all regions of the world, who perform their duties in the most independent way” (see Technical Secretariat: 10 June 2022 – NV/ODG-290/22 of OPCW document). 

June 12: In an interview with TASS, Russian Foreign Ministry representative Maria Zakharova indicated that Russia plans to invoke Article V of the Biological Weapons Convention. This move would trigger a meeting of the BWC States Parties for consultation about Russia’s allegations against the United States and Ukraine. “In the near future, we intend to activate mechanisms under Article V and VI of the Convention, which provide for consultations between the States Parties to the BTWC in resolving any issues regarding the purpose of the Convention or in connection with the implementation of its provisions, as well as cooperation in conducting any investigations into possible violations of obligations under the BTWC,” she said.

29 June: In a note verbale to the OPCW, Russia accused the Ukrainian Security Service (USS) of preparing a chemical provocation in order to blame Russia. The note verbale alleged that members of the USS arrived at a health resort in the Ukrainian town of Kurortny, Odessa Region, and “worked with the facility’s management on matters concerning the intake and placement of, and administration of medical aid to, victims of chemical exposure.” No additional evidence to support this accusation was provided. (See: Russian Federation: 25 July 2022 – NV_33).

June 29: Russia formally triggered the Article V mechanism of the Biological Weapons Convention. The treaty’s member states will now have to convene for a special summer session to hear Russia’s bio-lab allegations against the United States and Ukraine. 

July 5: In a note verbale submitted to the OPCW, Russia alleged that it had “reliable information” indicating that Ukrainian individuals were planning a chemical provocation in Nikolayevka, Donetsk, and further alleged that Ukrainians had already “brought containers of liquid chlorine into the water pumping and filtration unit of the Slavyansk thermal power plant and are planning to detonate them as Russian troops and units from the People’s Republic of Donetsk approach.” No evidence to back up this claim was provided in the note verbale. Russia also accused Ukraine of “creating the preconditions for the onset of manmade disaster” by using industrial facilities to house their troops and military equipment. Russia called on the member states of the OPCW to “exert influence” on Ukraine to prevent the use of chemical facilities by armed forces. (See: Russian Federation: 5 July 2022 – NV-34). Russia is currently facing international pressure to not use nuclear energy facilities to house troops and military equipment.

July 25: In a note verbale submitted to the OPCW, Russia alleged that “in the city of Konstantinovka, in the People’s Republic of Donetsk, Ukrainian nationalists have planted explosives on storage units holding radioactive and chemical waste from a metallurgy enterprise that produces lead,” and that “they plan to detonate these upon their retreat from the city.” The note verbale provided no evidence to back up this claim. (See: Russian Federation: 25 July 2022 – NV-37).

July 25: In another note verbale submitted to the OPCW on July 25, Russia alleged that, “at a fats and oils industrial complex in the city of Slavyansk, in the People’s Republic of Donetsk, personnel from the Ukrainian Security Service are planning to carry out the explosive destruction in the near future of containers holding a total of over 120 tonnes of hexane, a chemically hazardous substance.” The note verbale provided no evidence to back up the claim. (See: Russian Federation: 25 July – NV-38). 

28 July: Ukraine submitted a note verbale to the OPCW raising concerns about the shelling of chemical facilities and the risk of serious consequences if a civilian chemical facility is hit. (See: Ukraine: 28 July 2022 – NV_61219/35-196/50-55446). 

August 3: The United Nations Office for Disarmament Affairs announced that a consultative meeting to discuss Russia’s allegations against the United States and Ukraine will be held on August 26, continuing on September 5, 6, 7, and 9. 

August 20: Russia’s defense ministry accused Ukraine of “chemical terrorism” after an undisclosed number of Russian soldiers in the Zaporizhzhia region were taken to a hospital and tests showed botulinum toxin type B in their bodies. Ukraine denied the accusation and countered that the illness could have been caused by expired canned meat.

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Timeline of Syrian Chemical Weapons Activity, 2012-2022

May 2021

Contact: Daryl Kimball, Executive Director, 202-463-8270 x107; Kelsey Davenport, Director for Nonproliferation Policy, 202-463-8270 x102.

In July 2012, Syria publicly acknowledged that it possesses chemical weapons. For a number of years preceding this announcement, the U.S. intelligence community assessed that Syria has a stockpile of chemical weapons, including blister agents such as mustard gas, and nerve agents such as sarin and VX. Syria has the capability to deliver these agents using aerial bombs, ballistic missiles, and artillery rockets. An Organisation for the Prohibition of Chemical Weapons-UN joint investigative team found Syria and the Islamic State responsible for numerous chemical weapons attacks in Syria over the past several years.

Below is a timeline of significant events related to Syria’s chemical weapons program from July 2012 to the present.

Skip to: 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022


July 23, 2012: Syrian Foreign Ministry spokesman Jihad Makdissi confirmed for the first time that Syria has chemical weapons, stating that these weapons would never be used against the Syrian people, but only against “external aggression.”

August 20, 2012: President Barack Obama articulated his red-line regarding the use of chemical weapons in Syria. Obama said his calculations on a military response would change significantly if the United States sees “a whole bunch of chemical weapons moving around or being utilized.”

August 23, 2012: An official in the State Department confirmed that “Syria has a stockpile composed of nerve agents and mustard gas” and that the U.S. government monitors Syria’s chemical weapons activities “very closely.”

December 23, 2012: The first allegation of  chemical weapons use was reported. Seven people were allegedly killed in Homs by a “poisonous gas” used by the Assad regime. The coverage included the report of side effects such as nausea, relaxed muscles, blurred vision, and breathing difficulties.


January 15, 2013: A secret State Department cable from the U.S. consul general in Istanbul said there was compelling evidence that the Syrian military had used a chemical weapon known as Agent 15 in Homs on December 23, 2012.

January 16, 2013: Tommy Vietor, a spokesman for the National Security Council, said that the alleged incident of chemical weapons use in December was not consistent with information that the White House has about Syria’s chemical weapons program.

March 19, 2013: Alleged chemical weapons attacks were reported in Syria’s two main cities, the Khan al-Assel neighborhood of Aleppo and the Damascus suburb of al-Atebeh. About 25 people reportedly were killed and dozens more injured. The Assad regime claimed that Syrian opposition forces used chemical weapons in the fighting there.

March 20, 2013: The Syrian government requested the United Nations conduct an investigation of the March 19 attack on Aleppo, claiming that opposition forces used chemical weapons and killed 25 people.

President Obama said in a press conference with Israeli Prime Minister Netanyahu that “the use of chemical weapons is a game changer,” in Syria.

March 21, 2013: UN Secretary-General Ban Ki-moon announced the United Nations will conduct an investigation on the possible use of chemical weapons in Syria, in conjunction with the World Health Organization (WHO) and the Organisation for the Prohibition of Chemical Weapons (OPCW). Prior to the announcement, France and the United Kingdom sent letters to the Secretary-General, calling for investigations into three alleged incidents of the use of chemical weapons in Syria.

March 24, 2013: Syrian opposition activists reported that Syrian forces used chemical weapons from multiple rocket launchers at the town of Adra, northeast of Damascus, alleging two deaths and 23 injuries. Doctors described that the weapons used were phosphorus bombs that harm the nervous system and induce imbalance and loss of consciousness.

April 13, 2013: Syrian Observatory for Human Rights (SOHR) said that the Syrian army dropped two gas bombs on rebel-controlled Aleppo, killing two people and wounding 12. Opponents of the Syrian government accused the army of using chemical weapons.

April 17, 2013: UN Secretary-General Ban Ki-moon stated that Syria has impeded the UN investigation by failing to agree to the scope of the UN inquiry on chemical weapons use.

April 25, 2013: A letter sent to Sens. Carl Levin (D-Mich.) and John McCain (R-Ariz.) from the U.S. intelligence community said that the Assad regime may have used the nerve agent sarin “on a small scale” in Syria, but that the United States needs more evidence to provide “some degree of certainty” for any decision-making on further action. The letter also said that the Assad regime maintains custody of the chemical weapons in Syria.

April 26, 2013: President Obama remarked that the United States and the international community will work together to gain “strong evidence” of the Assad regime’s use of chemical weapons.

April 29, 2013: A helicopter dropped canisters allegedly containing chemical weapons on the town of Saraqeb. Eight people claimed symptoms such as nausea and breathing problems, and one of them later died.

June 4, 2013: French Foreign Minister Laurent Fabius asserted that there was “no doubt” that the Syrian regime used sarin in multiple cases. Fabius said that the French government confirmed the use of sarin by testing specimen taken from Syria. A UN report also said that there are “reasonable grounds” to have confidence in Syria’s use of chemical weapons four times in March and April, although the report cannot specify the chemical agents or verify who used them.

June 13, 2013: The White House said that the U.S. intelligence community has “high confidence” that the Assad regime attacked opposition forces by using chemical weapons multiple times over the past year. In the statement, Ben Rhodes, deputy national security adviser for strategic communications, said that physiological samples from multiple sources show exposure to chemical weapons. The evidence of use is recognized as “credible” in the statement.

August 14, 2013: Assad agreed to allow the UN inspection team into Syria to investigate three possible uses of chemical weapons. The team’s mandate only allows it to establish whether or not chemical weapons were used, not who used them.

August 21, 2013: Syrian opposition activists claimed that a large-scale chemical weapons attack occurred at the suburbs of the Ghouta region, where Syrian forces had been attempting to expel rebel force. Reports said that thousands of victims of the attack have been counted in the Damascus suburbs, whose symptoms were typically body convulsion, forming from mouths, blurry vision and suffocation. Although the number of victims has not been clarified yet, it is estimated to exceed 1,000 people, many of whom were non-combatants.

The United Nations Security Council also held an emergency meeting regarding the attack. The meeting produced a statement demanding further clarity of the incident.

August 23, 2013: UN Secretary-General Ban Ki-moon’s spokesperson expressed the intention of the UN to conduct “a thorough, impartial and prompt investigation” on the alleged chemical weapons attack in Syria on August 21.

The OPCW Director General, Ambassador Ahmet Üzümcü, expressed grave concerns about the latest attack in Syria, and said that the OPCW experts were already in Syria with the UN investigation team.

August 25, 2013: The Syrian regime announced that it will let the UN inspection team investigating past incidents of chemical weapons use visit the Damascus sites in the following days.

August 26, 2013: The U.S. Secretary of State John Kerry said in his press briefing that all information the U.S. has, including reports of the number of victims, their symptoms, and the firsthand accounts from humanitarian organizations, strongly indicate that chemical weapons were used in Syria. He also said that Syria attempted to cover-up the incident in the days following the attack.

Syrian President Bashar Assad announced that his army did not use chemical weapons in the August 21 attack in Damascus. Assad recognized the allegation of his use of chemical weapons as “politically motivated," in his meeting with Russia's Izvestia daily.

A convoy transporting the UN investigation team of chemical weapons was attacked by snipers in Syria. No UN personnel were injured, but they were unable to visit all of the sites affected by the attack.

August 28, 2013: The United States has concluded that the Assad regime conducted chemical weapons attacks against civilians, President Obama said in “PBS NewsHour.” Obama said he had not yet made a decision whether to take a military action in Syria.

A second UN Security Council meeting was held.

August 29, 2013: The British Parliament voted against supporting military action in Syria. Before the vote, a report from the Joint Intelligence Committee released a report which stated that chemical weapons were used in the August 21 attach, and that it was "highly likely" that the Assad regime was responsible.

August 30, 2013: The White House released the U.S. Government Assessment on the use of chemical weapons in Syria on August 21. The report says that the intelligence community has "high confidence" that the Syrian government used chemical weapons against the opposition elements in Damascus. Secretary Kerry, in an address, also said that the regime used chemical weapons "multiple times" over the past year. Kerry said discussions on military action are underway. The U.S. Government Assessment included this map of Damascus and the areas impacted by the alleged August 21 chemical weapons attack.

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August 31, 2013: President Obama made a statement saying that he would seek an authorization for the use of force from Congress for a limited military strike in Syria. Given the evidence of chemical weapons use by the Assad regime in the August 21 attack, Obama said he supported limited action in order to deter further chemical weapons use and uphold international norms.

September 2, 2013: France released its declassified intelligence assessment, which concluded that the Assad regime used Sarin gas in the August 21 attack, and in two earlier attacks in April. The report also said France assessed that the use of chemical weapons by the Assad regime violated the 1925 Geneva Protocol.

September 9, 2013: Russian Foreign Minister Sergey Lavrov announced a Russian proposition whereby Syria would agree to place its chemical weapons under international control and dismantle them and the United States would agree not to conduct a military strike on the country. Prior to the Russian announcement, Secretary of State Kerry, speaking in the United Kingdom, suggested that if the Assad regime turned over all of its chemical weapons to the international community "without delay", a military strike could be averted. Speaking to media outlets after Secretary Kerry, President Barack Obama said that the United States would consider the plan.

September 10, 2013: Syrian Foreign Minister Walid al-Moallem said that the Assad regime welcomed discussion on Russia's plan to give up Syria's chemical weapons and join the Chemical Weapons Convention. President Barack Obama, French President Francois Hollande, and British Prime Minister David Cameron discussed how to implement the plan through the UN Security Council, with France beginning to draft a resolution based on the Russian proposal, but with stipulations that force be authorized if Assad fails to implement the provisions of the resolution.

President Obama, in an address to the nation, also requested that Congress postpone a vote on the use of force while the diplomatic path proposed by the Russians is pursued in the UN Security Council. However, he also reiterated his commitment to pursue military action if a deal on securing Syria's chemical weapons is not reached.

September 12, 2013: The Assad regime sent a letter to the United Nations Secretary General which said that Assad signed a legislative decree providing the accession of Syria to the Chemical Weapons Convention. In the letter, Assad said Syria would observe its CWC obligations immediately, as opposed to 30 days from the date of accession, as stipulated in the treaty.

In Geneva, Secretary of State John Kerry met with his Russian counterpart, Foreign Minister Sergey Lavrov, to begin discussions of the Russian proposal for securing the Assad regime's chemical weapons.

September 14, 2013: U.S. Secretary of State John Kerry and Russian Foreign Minister Sergey Lavrov reached an agreement on a detailed plan for the accounting, inspection, control, and elimination of Syria’s chemical weapons. The plan requires Syria to provide a full declaration of its stockpile “within a week” and provide the OPCW and the UN access to all chemical weapons sites in Syria. The plan calls for the OPCW inspectors  to complete their initial inspections by November and calls for the destruction of the stockpile of chemical weapons and chemical agents by the first half of 2014. The United States and Russia secured approval of the plan by the OPCW executive council and then a UN Security Council resolution. The agreement outlined states that “in the event of non-compliance, including unauthorized transfer, or any use of chemical weapons by anyone in Syria, the UN Security Council should impose measures under Chapter VII of the UN Charter.

September 16, 2013: UN Secretary General Ban Ki Moon delivered a report on the UN investigation into the use of chemical weapons in Syria. The report concluded that chemical weapons were used against on August 21 on a "relatively large scale", and that the victims included civilians. The report cited evidence of the nerve agent sarin both in the environment and present in victims of the attack. It was outside of the report's mandate to assign blame for who used the chemical weapons.

September 20, 2013: In accordance with the terms of the agreement negotiated by the United States and Russia, Syria submitted a declaration of its stockpiles of chemical weapons to the OPCW.

September 27, 2013: The Executive Council of the OPCW adopted a timeline for destroying Syria's chemical weapons. Hours later, the United Nations Security Council unanimously voted to adopt a resolution that endorses the OPCW timeline for destroying Syria’s chemical weapons arsenal. The Security Council Resolution says that the body will impose measures under Chapter VII of its charter if Syria does not comply with the resolution, or uses or authorizes the transfer of any chemical agents.

October 1, 2013: A joint team of OPCW and UN officials arrived in Syria to begin destruction of the country's declared chemical weapons stockpiles and facilities.

October 6, 2013: Officials from the OPCW and UN team said that destruction of Syria's stockpiles of chemical weapons began. The officials confirmed that the Syrians will actually complete the destruction work, while the UN and OPCW team will monitor and verify the activities.

October 27, 2013: Syria submitted the details of its plans for "total and verified destruction" of its chemical weapons stockpile and production facilities to the OPCW. This declaration follows an initial declaration submitted on Sept. 20.

October 31, 2013: The OPCW confirmed that Syria destroyed, or rendered inoperable, all of its declared facilities for mixing and producing chemical weapons. The OPCW was able to inspect 21 of the 23 sites where these facilities were housed. The remaining two sites could not be visited due to security concerns, but inspectors said that the equipment was moved out of these sites and destroyed.

November 15, 2013: The OPCW Executive Council approved a plan for the elimination of Syria's stockpile of chemical weapons. The plan call for transporting the weapons outside of Syria and destruction of the chemical agents in a country that has yet to be identified. The "most critical" chemicals are to be transported out of Syria by December 31, 2013 and the remainder by February 5, 2014. The plan calls for the destruction no later than June 30, 2014, and the destruction of certain priority chemicals by March 15, 2014.

The Executive Council also announced that the OPCW was able to verify that 60 percent of Syrian declared, unfilled, munitions for chemical weapons delivery had been destroyed. Syria committed to destroying all of its unfilled munitions by January 31, 2014.

November 30, 2013: The OPCW announced that Syria's chemical weapons will be destroyed on a U.S. ship using hydrolysis. Hydrolysis is a process that breaks down chemical agents using hot water and other compounds to neutralize the agents.

December 12, 2013: The UN team led by Ake Sellstrom investigating incidents of chemical weapons use in Syria issued its final report to UN Secretary-General Ban Ki Moon. The report found that chemical weapons were likely used in five of the seven attacks investigated. The nerve agent sarin was likely used in four of the attacks, one of which was the large scale attack on a Damascus suburb in August.

December 31, 2013: Syria missed the deadline for sending all of its chemical weapons out of the country. This deadline was set by a UN Security Council Resolution approved in September.


January 7, 2014: Syria delivered the first load of chemical weapons to its port city Latakia. The chemical weapons were then loaded on a Danish ship that sailed out into international waters. China and Russia are providing protection for the ship, which will eventually transfer the cargo to the US ship, the MV Cape Ray, to be neutralized using hydrolysis.

January 9, 2014: The German government announced its willingness to assist in the disposal of the chemical waste byproduct that will be created from the hydrolysis process.

January 16, 2014: Italian Transport Minister Maurizio Lupi said that Gioa Tauro, a port in southern Italy, will be used to transfer Syrian chemical weapons to the US ship, the Cape Ray, that will neutralize the chemicals using hydrolysis.

January 27, 2014: A second shipment of Syrian chemical weapons was loaded onto Danish and Norwegian ships at the Syrian port of Lattakia. The U.S. ship that will receive the chemical weapons and then neutralize them using hydrolysis, the Cape Ray, left port. The chemicals will be transferred to the Cape Ray at the Italian port Gioa Tauro.

February 6, 2014: Sigrid Kaag, head of the UN/OPCW mission for destruction of Syria's chemical weapons, addressed the UN Security Council a day after Syria missed a second deadline for handing over its critical chemicals and said that she did not believe that the Assad regime was deliberately stalling the removal process. However, she urged Syria to speed up the shipments in order to meet the destruction deadline of June 30.

February 10, 2014: A third shipment of Syrian chemical weapons was loaded on a Norwegian cargo ship. In total, 11 percent of Syria's chemical weapons were shipped out of Syria.

February 14, 2014: The OPCW announced that two companies, one in Finland (Ekokem OY AB) and one in Texas (Veolia), were awarded contracts to dispose of the effluent created during the destruction of Syria's chemical weapons.

February 21, 2014: The OPCW executive committed met to consider the Assad regime's new proposal for shipping out its chemical weapons. After failing to meet a Feb. 5 deadline to remove all of its chemical weapons and precursor chemicals out of the country, the regime proposed a 100 day extension. The OPCW executive committee, however, said that it can be accomplished more quickly. The 100 day extension also will not allow the Cape Ray enough time to destroy the chemical weapons by the June 30 UN Security Council deadline.

February 25, 2014: The Assad regime delivered a shipment of mustard gas to the Syrian port of Latakia to be loaded onto ships.

March 4, 2014: The Assad regime submitted a revised proposal to remove its chemical weapons from Syria by the end of April 2014. Two additional shipments of chemical weapons also reached the port of Latakia and were loaded onto ships. In total, more than 35% of the country's chemical weapons have been removed.

March 7, 2014: The Executive Council concluded its 75th Session and noted in its report the “increasing pace” of removal of Syria’s chemical stockpile and requested the Syria continue “systematic, predictable and substantial movements” to complete the shipments.

Another shipment of priority 1 chemicals was reached the port of Latakia, bringing the total amount of chemical agents removed from Syria to 29 percent of the total stockpile.

March 19, 2014: The OPCW said that two additional shipments of Priority 1 and Priority 2 chemicals were delivered to the port of Latakia and loaded onto cargo vessels during the past week. Syria has now shipped out more than 45 percent of its stockpile.

April 4, 2014: The 12th shipment of Syrian chemical weapons reached the port of Latakia, according to the OPCW.

April 11, 2014: Reports emerged of an attack using chlorine-gas bombs in Kafr Zita, a village controlled by opposition forces in northwestern Syria.

April 14, 2014: The Syrian government delivered its 13th consignment of chemicals to Latakia, which was removed today from the port on cargo ships. As of this delivery, the OPCW said that the Assad regime has shipped out 65 percent of its total stockpile of chemical weapons, including 57 percent of the Priority 1 chemicals.

April 18, 2014: Additional shipments of chemical weapons reached the port of Latakia between April 14-18. The OPWC said in an April 18 statement that in total, the 16 shipments constitute about 80 percent of Syria's stockpile of chemical weapons.

April 22, 2014: Another shipment reached Latakia port, bringing the total of the chemical weapons stockpile removed from Syria to 86 percent.

April 24, 2014: An additional shipment to Latakia brings the total to 92 percent.

April 29, 2014: The OPCW announced that it would send a team to investigate the April 11 attacks that the Assad regime used chlorine gas.

May 1, 2014: Syria missed the revised deadline to remove all of its chemical weapons stockpile from the country by the end of April. Approximately 8 percent of the declared stockpile, largely sarin precursor chemicals, remains in Damascus.

June 8, 2014: The Norwegian ship Taiko departed for Finland and the United States to deliver Syrian chemical weapons for destruction.

June 17, 2014: The OPCW's fact finding mission in Syria to investigate the use of chlorine gas concluded that it was used in earlier attacks. The team was unable to visit all of the locations due security issues.

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June 23, 2014: OPCW Director General Uzumcu announced that the last 8 percent of Syria's declared chemical weapons stockpile was shipped out of the country from the port of Latakia on the Danish ship Ark Futura. Uzumcu says the chemicals should be destroyed within four months.

July 2, 2014: Over 600 metric tons of chemical weapons were loaded on to the Cape Ray at the port of Gioia Tauro in Italy.

July 21, 2014: The OPCW announced that all of the chemical weapons have reached the various facilities in Finland, the United States, the United Kingdom, or the Cape Ray for destruction. At the time of the announcement nearly 32 percent of the total stockpiles had been destroyed.

July 24, 2014: The executive council of the OPCW also announced that seven hangars in Syria that were part of the country's chemical weapons will be destroyed and five bunkers will be permanently sealed.

August 13, 2014: The OPCW announced that 581 metric tonnes of a precursor chemical for sarin gas have been neutralized on the Cape Ray. Operations to neutralize the blister agent sulfur mustard have now begun.

August 19, 2014: The Cape Ray completed destruction of 600 metric tons of Syrian chemical weapons and precursor chemicals. The OPCW announced that the ship will now transport the effluent to Finland and Germany for disposal at land-based facilities.

September 10, 2014: The OPCW confirmed that chlorine gas is being used in Syria. While the OPCW did not assign blame for the attacks, US Secretary of State John Kerry said that the use of helicopters to drops the chlorine gas "strongly points" to the Assad regime as the perpetrator.


March 6, 2015: The UN Security Council adopted a resolution March 6 condemning the use of chlorine as a weapon in Syria’s civil war and threatening action under Chapter VII of the UN Charter if chemical arms are used again.

April 16, 2015: Doctors testified at the UN Security Council about recent chlorine gas attacks in Syria. Human Rights Watch estimated that over 200 were killed by recent chlorine attacks.

May 8, 2015: Reuters reported that the OPCW confirms traces of sarin and VX gas at a military facility in Syria that were not declared. The samples were taken in December and January.

August 7, 2015: Security Council Resolution 2235 was adopted, creating an investigative unit to determine the responsible parties for reported chemical weapons attacks in Syria.


November 6, 2015: A press release from the OPCW fact-finding team claimed with "the utmost confidence" that the Islamic State used sulfur mustard in an attack on August 21, 2015 in Marea, in northern Syria.

January 4, 2016: The OPCW announced in a press release that the last of the declared Syrian chemical weapons material, 75 cylinders of hydrogen fluoride, had been destroyed by Veolia Environmental Services Technical Solutions.

August 10, 2016: Hospital officials reported a chemical weapons attack using chlorine gas in Aleppo.

August 24, 2016: The third report of the OPCW-UN Joint Investigative Mechanism was released, finding that the Syrian government was responsible for chemical weapons attacks in Talmenes in April 2014 and in Sarmin in March 2015. The report found that the Islamic State was responsible for an attack using sulfur mustard in Marea in August 2015.

September 7, 2016: Allegations were made that toxic chemicals, likely chlorine gas, were used in Aleppo. 

October 21, 2016: The OPCW-UN Joint Investigative Mechanism issued a report finding that the Syrian regime was responsible for a third attack using chlorine gas in Idlib province on March 16, 2015. 

November 11, 2016: The OPCW Executive Council adopted a decision that condemns the use of chemical weapons in Syria and calls upon parties responsible for use, as identified in the OPCW-UN Joint Investigate Mechanism reports, to desist from further attacks using chemicals. The decision called for additional investigations at Syria at sites identified by the UN-OPCW reports and inspection of facilities in Syria. 

December 13, 2016: Allegations were made that chemical weapons were used in the Islamic State controlled areas of the Hama Governate, northwest of Palmyra. 


April 4, 2017: Chemical weapons were used in an attack that killed dozens of people in Syria's northern Idlib province. Initial reports suggest the attack used sarin gas, a nerve agent. The attack is believed to have been perpetrated by the Syrian government, due to the type of aircraft in the area at the time. The OPCW announced that it is investigating the reports. Syria denied it was responsible. 

April 5, 2017: The UN Security Council called an emergency meeting to discuss the chemical weapons attack in Idlib. 

April 6, 2017: The United States used Tomahawk cruise missiles to target an air base in Syria. The Assad regime is believed to have conducted the April 4 chemical weapons attack from that base.  

April 11, 2017: The United States released a declassified report that confirmed victims were exposed to sarin in the April 4 attack. 

April 12, 2017: Russia vetoed a UN Security Council Resolution that condemned the April 4 chemical attack, called upon Syria to provide full access to investigators, and expressed determination to hold perpetrators accountable. Russia said that blame for the April 4 attack was prematurely attributed to the Assad regime. 

April 19, 2017: The OPCW said there was "incontrovertible" evidence that the April 4 attacks used sarin or a sarin-like substance. 

June 26, 2017: The White House issued a release saying it identified "possible preparations for another chemical weapons attack by the Assad regime." The statement said that Assad will "pay a heavy price" if he conducts an attack using chemical weapons. U.S. Ambassador to the UN Nikki Haley said in a separate statement that by supporting the Assad regime, Russia and Iran would also be accountable for any further use of chemical weapons. 

June 30, 2017: The OPCW fact-finding mechanism confirmed that sarin was used in a chemical weapons attack in Khan Sheikhoun on April 4, 2017.

October 24, 2017: The UN Security Council failed to adopt a resolution to extend the mandate of the OPCW-UN JIM for another year before it expires on November 17. Eleven members voted in favor of the resolution, China and Kazakhstan abstained and Boliva and Russia voted against it. The resolution did not pass because of Russia's veto.

October 26, 2017: The seventh report of the OPCW-UN joint investigative mechanism found the Assad regime guilty of using sarin nerve agent in the April 4 attack in Khan Sheikhoun and the Islamic State responsible for the use of sulfur mustard at Umm Hawsh in September 2016.

November 6, 2017: The OPCW Fact-Finding Mission reported that sarin was more than likely used as a chemical weapon on March 30, 2017 in the south of Ltamenah.

November 8, 2017: U.S. Secretary of State Rex Tillerson, U.K. Foreign Secretary Boris Johnson, French Foreign Minister Jean-Yves Le Drian and German Foreign Minister Sigmar Gabriel released a joint statement condemning the use of chemical weapons in Syria as described in the seventh JIM report and calling on the UN Security Council to act to continue the investigations. 

November 16, 2017: The mandate of the OPCW-UN JIM, responsible for determining the culpable actor for chemical weapons attacks in Syria, expired after both resolutions introduced at the UN Security Council to extend it failed. The resolution sponsored by the United States received 11 votes in favor, 2 against and 2 abstentions and failed because Russia vetoed it. The Russian resolution received 4 votes in favor, 7 against and 4 abstentions.

November 17, 2017: A UN Security Council resolution introduced by Japan to extend the JIM's mandate for 30 days received 12 votes in favor but failed because of a Russian veto. 


January 23, 2018: France launched the International Partnership Against Impunity for the Use of Chemical Weapons, a new initiative that seeks to increase information sharing about reported chemical weapons attacks and publically lists individuals and entities sanctioned for their involvement in chemical weapons use. Russia then called a last minute UN Security Council meeting, introducing a new proposal to extend the Joint Investigative Mechanism (JIM). The United States rebuked the proposal on the grounds that it was merely intended as a distraction from the launch of the new partnership.

February 1, 2018: The third chemical weapon attack in 2018 in Douma, Damascus is reported. The two earlier attacks were reported on January 13 and January 22. Reports assess that chlorine gas was used in all attacks. At a UN Security Council briefing on February 5, UN High Representative for Disarmament Affairs Izumi Nakamitsu stated that reports from the OPCW Fact-Finding Mission on these alleged attacks are pending.

April 7, 2018: Reports surfaced of a major chemical weapons attack in Douma, a suburb outside of Damascus, Syria, killing at least several dozen civilians. This followed smaller chlorine gas attacks that were reported in Douma on March 7 and 11. Human Rights Watch has documented 85 chemical weapons attacks since 2013 in Syria. The OPCW announced that its Fact Finding Mission is investigating the incident to determine which chemical weapons may have been used.

April 10, 2018: The UN Security Council voted on three resolutions to address chemical weapons use in Syria. Russia vetoed a U.S.-sponsored resolution which would have created a UN Independent Mechanism of Investigation with a one-year mandate to investigate the responsible actors for chemical weapons use in Syria. A Russian resolution which would have created a similar body but would have allowed the UN Security Council, not the investigative body, to ultimately determine accountability failed to receive enough votes to pass. A second Russian resolution, which urged the OPCW Fact Finding Mission to investigate the incident and offered Russian military protection for investigators, also failed to receive enough votes to pass. The OPCW had already announced earlier that day that it was planning to deploy a Fact-Finding Mission to Douma. 

April 13, 2018: The UN Security Council met for the fourth time that week to discuss chemical weapons use in Syria. Russia and Bolivia continued to urge the United States against taking unilateral military action as the United States, France and the United Kingdom seemed to make the case for a strike. "Should the United States and our allies decide to act in Syria, it will be in defense of a principle on which we all agree, U.S. UN Ambassador Nikki Haley said.

France, the United Kingdom and the United States launched precision strikes on three Syrian chemical weapons facilities. In a televised address to the nation, President Trump explained that the purpose of the strike was to "establish a strong deterrent against the production, spread and use of chemical weapons." He continued "To Iran and Russia, I ask: What kind of a nation wants to be associated with the mass murder of innocent men, women and children?" Syrian state television reported that its air defense system had shot down 13 of the missiles, although the United States later denied that any missiles had been engaged. Russian Ambassador Anatoly Antonov said in a statement shortly after the announcement of the strike: "We warned that such actions will not be left without consequences."

April 14, 2018: The OPCW Fact-Finding Mission was in Syria investigating the April 7 chemical weapons attack to verify that the attack occurred and to identify which chemical agent was used. 

France released its national assessment of the April 7 chemical weapons attack, concluding that "(i) beyond possible doubt, a chemical attack was carried out against civilians at Douma on 7 April 2018; and (ii) that there is no plausible scenario other than that of an attack by Syrian armed forces as part of a wider offensive in the Eastern Ghouta enclave."

The UN Security Council met to discuss the situation in Syria. The United Kingdom stated that the legal basis for its joint strike was humanitarian intervention. Russia and Bolivia condemned the strike, which they asserted was a violation of the UN Charter. Russia also introduced a draft resolution which condemned "aggression against the Syrian Arab Republic by the US and its allies," but it only received three votes and failed to pass. France, the United Kingdom and the United States announced their intention to introduce a draft resolution on political and humanitarian tracks to resolve the conflict.

April 21, 2018: The OPCW Fact-Finding mission team visited one of the sites in Douma to collect samples for analysis in connection with the April 7 attack. 

May 16, 2018: The OPCW Fact-Finding mission reported that "chlorine, released from cylinders through mechanical impact, was likely used as a chemical weapon on 4 February 2018 in the Al Talil neighborhood of Saraqib."

June 13, 2018: The OPCW Fact-Finding mission reported that sarin was "very likely used as a chemical weapon" in Ltamenah, Syria on March 24, 2017 and that chlorine was "very likely used as a chemical weapon" at and around Ltamenah Hospital on March 25, 2017.

June 27, 2018: A special session of the OPCW conference of states-parties voted to grant the OPCW the mandate to investigate and attribute responsibility for chemical weapons attacks in Syria confirmed by the Fact-Finding Mission.

September 12, 2018: The Independent International Commission of Inquiry on the Syrian Arab Republic, established in 2011 by the UN Human Rights Council reported that the Syrian government used chlorine as a weapon four times from January to July 2018.


March 1, 2019: The OPCW Fact-Finding Mission released a final report concluding that a toxic chemical, likely chlorine, was used as weapon on April 7, 2018 in Douma, Syria. The OPCW had issued an interim report on the incident in July 2018. 

May 19, 2019: The United States alleged that the Syrian government used chlorine in an attack in the Idlib area.

May 28, 2019: Responding to news of the unauthorized disclosure by a former OPCW official of an internal document related to the organisation’s investigation in Douma, the OPCW Director-General launches an independent investigation into possible breaches of confidentiality.

September 26, 2019: The United States announced the results of its investigation into the May 19, 2019 attack and concluded that the Syrian government used chemical weapons.


January 20, 2020: Russia held an open United Nations Arria-formula meeting on the OPCW Douma report. In his remarks to the press, Russian Permanent Representative Vassily Nebenzia said there is “high probability” that the March 2019 Fact-Finding Mission report on the OPCW investigation in Douma was “fabricated.”

U.S. Acting Deputy Permanent Representative Cherith Norman Chalet condemned Russia for a "blatant attempt to use a Security Council meeting to weaken the credibility of the OPCW and its findings on the Douma attack" and reaffirmed U.S. support for the March 2019 Fact-Finding Mission report.

February 6, 2020: The OPCW released the findings of its independent investigation into possible breaches of confidentiality which commenced after a former OPCW official released a document alleging that the March 2019 Fact-Finding Mission report was fabricated. The OPCW concluded that the dissenting official and a colleague, who knew of the document ahead of its release, had “failed to protect confidential information related to the Douma FFM investigation” and the information was “misused to call into question the Organisation’s competence and credibility.”

OPCW Director-General Fernando Arias reaffirmed the March 2019 Fact-Finding Mission report’s conclusion that a chemical weapon was used in Douma in April 2018.

April 8, 2020: The OPCW releases the first report by its Investigation and Identification Team (IIT), which attributes responsibility for a series of chemical weapons attacks in March 2017 to the Syrian Arab Republic's Air Force.

May 12, 2020: A closed-setting Informal Interactive Dialogue (IID) is held via teleconference between members of the United Nations Security Council and high-ranking officials from the Organisation for the Prohibition of Chemical Weapons (OPCW) to discuss the use of chemical weapons in Syria. The dialogue focuses on the OPCW’s April 2020 report that blames the Syrian air force for three chemical incidents in the town of Ltamenah, Syria, in March 2017.

Russia and China boycott the IID. Russia’s ambassador to the United Nations, Vassily Nebenzia, condemns the meeting’s closed setting as contradictory to “the slogans of openness and transparency of the Security Council.” China does not comment on the meeting.

July 9, 2020: At the 94th Session of the Executive Council of the OPCW, the council passed EC-94/DEC.2 "Addressing the Possession and Use of Chemical Weapons by the Syrian Arab Republic." The decision was in response to the 8 April 2020 Investigation and Identification Team (IIT) report. It gave Syria 90 days to declare any chemical weapons and CW facilities - in particular, those related to the March 2017 CW attacks - and resolve all outstanding issues regarding its initial declaration of its chemical weapons stockpile and program.

July 20, 2020: OPCW Director General Fernando Arias sent a letter to the Deputy Foreign Minister of the Syrian Arab Republic, H.E. Dr. Faisal Mekdad, to outline the obligations of the Syrian Arab Republic under ED-94/DEC.2 and to indicate the readiness of the Secretariat to assist the Syrian Arab Republic in fulfilment of these obligations. 

October 14, 2020: The Director General of the OPCW, H.E. Fernando Arias, released a report stating that Syria had not made progress on any of the measures detailed in EC-94/DEC.2 within the 90 day timeframe. 


April 12, 2021: The OPCW releases the second report by its Investigation and Identification Team (IIT). The IIT concluded "there were reasonable grounds to believe that, at approximately 21:22 on February 2018, a military helicopter of the Syrian Arab Air Force under the control of the Tiger Forces hit eastern Saraqib by dropping at least one cylinder. The cylinder ruptured and released chlorine over a large area, affecting 12 named individuals." 

The U.S. State Department expressed its support for the findings of the report in a press release: "The United States concurs with the OPCW's conclusions cited in this report" and "support the impartial and independent work of the OPCW."

April 16, 2021: Russia held an open United Nations Security Council Arria-formula meeting following the release of the OPCW's IIT report. During the meeting, which was titled "Protection of Developing Nations Against Political Pressure: Upholding the Integrity of International Non-Proliferation Regimes," several speakers questioned the work of the OPCW's Fact Finding Mission and Investigation and Identification Teams.

Russia's ambassador to the United Nations, Vassily Nebenzia, alleged that his Western colleagues were "attempt[ing] to mobilize public opinion against Syria authorities with a sole purpose. And it is not about upholding non-proliferation regime. It is all about regime change."  


April 20-22, 2021: At the second session of the 25th Conference of the States Parties to the Chemical Weapons Convention, the member states passed a decision that suspended Syria's rights and privileges under the Convention. This means that, until Syria completes the measures laid out in EC-94/DEC.2, Syria is not able to vote or hold any office in the Conference or Executive Council. 


January 26, 2022: The Fact-Finding Mission of the Organization for the Prohibition of Chemical Weapons published a report concluding there were reasonable grounds to believe that on September 1, 2015 in Marea, Syria, a chemical blister agent was used as a weapon.

February 1, 2022: The Fact-Finding Mission of the Organization for the Prohibition of Chemical Weapons published a report concluding were reasonable grounds to believe that an industrial chlorine cylinder was used as a chemical weapon on October 1, 2016, in Kafr Zeita, Syria. 

Updated by Julia Masterson and Leanne Quinn

Strategic Arms Control and Policy

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March 2022

Contact: Kelsey Davenport, Director for Nonproliferation Policy, (202) 463-8270 x102

The Biological Weapons Convention (BWC) currently has 183 states-parties, including Palestine, and four signatories (Egypt, Haiti, Somalia, and Syria). Ten states have neither signed nor ratified the BWC (Chad, Comoros, Djibouti, Eritrea, Israel, Kiribati, Micronesia, Namibia, South Sudan, and Tuvalu). The BWC opened for signature on April 10, 1972, and entered into force on March 26, 1975. A country that did not ratify the BWC before it entered into force may accede to it at any time.

For a guide to the terms of the convention, see The Biological Weapons Convention (BWC) at a Glance.

Country Signature Ratification/Accession
Afghanistan 4/10/72
Albania -
Algeria -
Andorra -
Angola -
Antigua & Barbuda - 1/29/03
Argentina 8/1/72 11/27/79
Armenia -
Australia 4/10/72
Austria 4/10/72
Azerbaijan -
Bahamas - 11/26/86
Bahrain -
Bangladesh -
Barbados 2/16/73 2/16/73
Belarus 4/10/72
Belgium 4/10/72
Belize [1] - 10/20/86
Benin 4/10/72
Bhutan -
Bolivia 4/10/72
Bosnia and Herzegovina [2] -
Botswana 4/10/72
Brazil 4/10/72
Brunei Darussalam -
Bulgaria 4/10/72
Burkina Faso -
Burundi 4/10/72
Cambodia 4/10/72
Cameroon - 1/18/13
Canada 4/10/72
Cape Verde -
Central African Republic 4/10/72 9/25/18
Chile 4/10/72
China -
Colombia 4/10/72
Congo -
Cook Islands - 12/4/08
Costa Rica 4/10/72
Côte d'Ivoire 5/23/72
Croatia [2] -
Cuba 4/12/72
Cyprus 4/10/72
Czech Republic [3] -
Democratic Republic of Congo [4] 4/10/72
Denmark 4/10/72
Dominica -
Dominican Republic 4/10/72
Ecuador 6/14/72
Egypt 4/10/72 -
El Salvador 4/10/72
Equatorial Guinea -
Estonia -
Eswatini -
Ethiopia 4/10/72
Fiji 2/22/73
Finland 4/10/72
France -
Gabon 4/10/72
Gambia 6/2/72
Georgia -
Germany [5] 4/10/72
Ghana 4/10/72
Greece 4/10/72
Grenada -
Guatemala 5/9/72
Guinea   11/9/16
Guinea-Bissau -
Guyana 1/3/73
Haiti 4/10/72
Holy See 1/4/02
Honduras 4/10/72
Hungary 4/10/72 12/27/72
Iceland 4/10/72
India 1/15/73
Indonesia 6/20/72
Iran 4/10/72
Iraq 5/11/72 6/19/91
Ireland 4/10/72 10/27/72
Italy 4/10/72
Jamaica -
Japan 4/10/72
Jordan 4/10/72
Kazakhstan -
Kenya -
Kuwait 4/14/72
Kyrgyzstan - 10/15/04
Laos 4/10/72
Latvia -
Lebanon 4/10/72 3/26/75
Lesotho 4/10/72
Liberia 4/10/72
Libya 4/10/72 1/19/82
Liechtenstein -
Lithuania -
Luxembourg 4/10/72
Madagascar 10/13/72
Malawi 4/10/72
Malaysia 4/10/72
Maldives -
Mali 4/10/72
Malta 9/11/72
Marshall Islands   11/15/12
Mauritania   1/28/15
Mauritius 4/10/72
Mexico 4/10/72
Moldova - 1/28/05
Monaco -
Mongolia 4/10/72
Montenegro [6] -
Morocco 5/2/72
Mozambique - 3/29/11
Myanmar 4/10/72  12/1/14
Nauru - 3/5/13
Nepal 4/10/72
Netherlands 4/10/72
New Zealand 4/10/72
Nicaragua 4/10/72
Niger 4/21/72
Nigeria 7/3/72
Niue   6/14/18
North Korea - 3/13/87
North Macedonia [2] -
Norway 4/10/72
Oman -
Pakistan 4/10/72
Palau - 2/20/03
Palestine - 1/9/18
Panama 5/2/72 3/20/74
Papua New Guinea -
Paraguay -
Peru 4/10/72
Philippines 4/10/72
Poland 4/10/72
Portugal 6/29/72
Qatar 11/14/72
Romania 4/10/72
Russia [7] 4/10/72
Rwanda 4/10/72
St. Kitts & Nevis -
St. Lucia [8] -
St. Vincent & the Grenadines [8] -
Samoa   9/21/17
San Marino 9/12/72
Sao Tome and Principe - 8/24/79
Saudi Arabia 4/12/72
Senegal 4/10/72
Serbia [2] [6] - 4/27/92
Seychelles -
Sierra Leone 11/7/72
Singapore 6/19/72
Slovakia [3] -
Slovenia [2] -
Solomon Islands [8] -
Somalia 7/3/72 -
South Africa 4/10/72
South Korea 4/10/72
Spain 4/10/72
Sri Lanka 4/10/72
Sudan -
Suriname -
Sweden 2/27/74
Switzerland 4/10/72
Syria 4/14/72 -
Tajikistan - 6/27/05
Tanzania 8/16/72
Thailand 1/17/73
Timor Leste - 5/5/03
Togo 4/10/72
Tonga - 9/28/76
Trinidad & Tobago - 7/19/07
Tunisia 4/10/72
Turkey 4/10/72
Turkmenistan - 1/11/96
Uganda -
Ukraine 4/10/72
United Arab Emirates 9/28/72
United Kingdom 4/10/72
United States 4/10/72
Uruguay -
Uzbekistan -
Vanuatu -
Venezuela 4/10/72
Vietnam 4/10/72
Yemen [9] 4/26/72
Zambia -
Zimbabwe -

Taiwan (the Republic of China) has also stated its intent to abide by the treaty, despite not being a state party. The Republic of China signed the treaty on April 10, 1972 and ratified it on February 9, 1973.

Source: UN Website

Research assistance by Marissa Papatola


1. Succession from the United Kingdom

2. Succession from Yugoslavia

3. Succession from Czechoslovakia

4. Ratification as Zaire

5. Ratification as East Germany and West Germany

6. Ratified as Serbia and Montenegro

7. Ratified as the Soviet Union

8. Succession from the United Kingdom

9. Ratified as South Yemen and North Yemen

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The Biological Weapons Convention (BWC) At A Glance

February 2022

Contact: Daryl Kimball, Executive Director, (202) 463-8270 x107


The Biological Weapons Convention (BWC) is a legally binding treaty that outlaws biological arms. After being discussed and negotiated in the United Nations' disarmament forum starting in 1969, the BWC opened for signature on April 10, 1972, and entered into force on March 26, 1975. It currently has 183 states-parties, including Palestine, and four signatories (Egypt, Haiti, Somalia, Syria, and Tanzania). Ten states have neither signed nor ratified the BWC (Chad, Comoros, Djibouti, Eritrea, Israel, Kiribati, Micronesia, Namibia, South Sudan and Tuvalu).

Terms of the Treaty

The BWC bans:

  • The development, stockpiling, acquisition, retention, and production of:
    1. Biological agents and toxins "of types and in quantities that have no justification for prophylactic, protective or other peaceful purposes;"
    2. Weapons, equipment, and delivery vehicles "designed to use such agents or toxins for hostile purposes or in armed conflict."
  • The transfer of or assistance with acquiring the agents, toxins, weapons, equipment, and delivery vehicles described above.

The convention further requires states-parties to destroy or divert to peaceful purposes the "agents, toxins, weapons, equipment, and means of delivery" described above within nine months of the convention's entry into force. The BWC does not ban the use of biological and toxin weapons but reaffirms the 1925 Geneva Protocol, which prohibits such use. It also does not ban biodefense programs.


The treaty regime mandates that states-parties consult with one another and cooperate, bilaterally or multilaterally, to solve compliance concerns. It also allows states-parties to lodge a complaint with the UN Security Council if they believe other member states are violating the convention. The Security Council can investigate complaints, but this power has never been invoked. Security Council voting rules give China, France, Russia, the United Kingdom, and the United States veto power over Security Council decisions, including those to conduct BWC investigations.

Membership and Duration

The BWC is a multilateral treaty of indefinite duration that is open to any country. 


The convention has been flagrantly violated in the past. The Soviet Union, a state-party and one of the convention's depositary states, maintained an enormous offensive biological weapons program after ratifying the BWC. Russia says that this program has been terminated, but questions remain about what happened to elements of the Soviet program. Iraq violated its commitments as a signatory state with its biological weapons program, which was uncovered by the UN Special Commission on Iraq after the Persian Gulf War. Iraq became a state-party after the war.

In November 2001, the United States publicly accused Iraq, as well as member state North Korea, of breaching the convention's terms. Washington also expressed concern about compliance by Iran and Libya, which are also states-parties, and by Syria. The United States itself raised concerns in 2001 about whether some of its activities, ostensibly being conducted as part of its biodefense program, are permitted under the BWC. In 2002, Washington added Cuba, also a state-party, to its list of countries conducting activities that violate the convention.

According to the U.S. State Department 2021 Compliance Report, Russia “maintains an offensive BW program and is in violation of its obligation under Articles I and II of the BWC.”

The United States certified North Korea in noncompliance with the BWC in 2021, and assessed it “does not have sufficient information” to determine whether China is in compliance with its obligation to eliminate its biological weapons stockpile under the BWC.

The 2021 U.S. Compliance Report also noted that Iran’s activities continue to “raise concerns regarding its compliance with Article I of the BWC,” and that it is “unable to differentiate some of Iran’s public health research and biodefense activities from those that are prohibited under the BWC.”

Review Conferences

States-parties have convened a review conference about every five years to review and improve upon the treaty's implementation.

Second Review Conference

In an effort to enhance confidence and promote cooperation among states-parties, at the second BWC review conference in 1986 member states agreed to implement a set of confidence-building measures. Under these politically binding measures, states should:

  • Exchange data on high-containment research centers and laboratories or on centers and laboratories that specialize in permitted biological activities related to the convention.
  • Exchange information on abnormal outbreaks of infectious diseases.
  • Encourage the publication of biological research results related to the BWC and promote the use of knowledge gained from this research.
  • Promote scientific contact on biological research related to the convention.

Third Review Conference

At the third BWC review conference in 1991, the scope of the first measure was expanded to include national biological defense programs and the second and fourth measures were slightly modified. In addition, three more measures were added to this list. States should:

  • Declare legislation, regulations, and "other measures" pertaining to the BWC.
  • Declare offensive or defensive biological research and development programs in existence since January 1, 1946.
  • Declare vaccine production facilities.

These endeavors have been largely unsuccessful; the vast majority of states-parties have consistently failed to submit declarations on their activities and facilities.

The 1991 review conference also tasked a group of "governmental experts" to evaluate potential verification measures for use in a future compliance protocol to the BWC. The group subsequently considered 21 such measures and submitted a report to a special conference of states-parties in 1994. Building off this report, the conference tasked a second body, known as the Ad Hoc Group, with negotiating a legally binding protocol to the BWC to strengthen the convention.

Ad Hoc Group

The Ad Hoc Group met from January 1995 to July 2001 and aimed to finish its work before the fifth review conference, which began in November 2001. During the course of the negotiations, the group developed a protocol that envisioned states submitting to an international body declarations of treaty-relevant facilities and activities. That body would conduct routine on-site visits to declared facilities and could conduct challenge inspections of suspect facilities and activities as well.

However, a number of fundamental issues—such as the scope of on-site visits and the role export controls would play in the regime—proved difficult to resolve. In March 2001, the Ad Hoc Group's chairman issued a draft protocol containing language attempting to strike a compromise on disputed issues. But in July 2001, at the Ad Hoc Group's last scheduled meeting, the United States rejected the draft and any further protocol negotiations, claiming such a protocol could not help strengthen compliance with the BWC and could hurt U.S. national security and commercial interests.

Fifth Review Conference

The fifth BWC review conference, which many experts thought could resolve the fate of the Ad Hoc Group, was suspended on its last day, December 7, 2001, after the United States tabled a controversial proposal to terminate the Ad Hoc Group's mandate and replace it with an annual meeting of BWC states parties. The United States was the only country that favored revoking the group's mandate. The states parties resumed the fifth review conference in November 2002, but failed to agree on any verification measures, including the proposed protocol.

Sixth Review Conference

The sixth BWC review conference, which met between November 20 and December 8, 2006, was the was the first successful review conference since 1996, reaching agreement on a final document

The conference produced a list of four work programs held each successive year until the next review conference in 2011.

Some issues that enjoyed broad-based support did not make it into the work program. The United States and Russia opposed proposals to reform confidence-building measures on the basis that participation in the existing mechanisms is poor. Russia was the primary factor behind bio-terrorism being dropped from the list of agenda items.

States parties did agree to address the BWC’s institutional deficit through the creation of the Implementation Support Unit (ISU), which is staffed by three permanent employees based in Geneva. The permanent staff members will be paid by the BWC and will be housed in the UN Department of Disarmament Affairs in Geneva. Previously, the BWC review conference was only supported on a part-time basis.

The ISU’s mandate is to provide administrative support for the BWC as well as facilitating confidence-building measures between states parties. The ISU will, among other things, serve to ease communication between states parties, as well as compile and disseminate confidence-building measures submitted from states parties.

Since the conclusion of the 2006 review conference the ISU has been strengthened in terms of budget and staff. Despite initial U.S. opposition, an EU proposal to allow states parties to make additional, voluntary contributions to the ISU was accepted during the 2007 annual meeting. The United States originally objected to the proposal on the grounds that it would increase the responsibility of the ISU. However, this problem was resolved through a statement stressing that the ISU has only three staff members, and any contributions are only designed to assist the ISU in completing its mandate. During the 2008 meeting of states parties, the EU provided a $2 million dollar donation to the ISU in order to pay for two additional staff members for the following two years. The two new staff are officially assigned to the UN Office for Disarmament Affairs, to avoid any conflict over a perceived expansion of ISU.

Seventh Review Conference

The seventh BWC review conference was held in December 2011. The Final Declaration document concluded that “under all circumstances the use of bacteriological (biological) and toxin weapons is effectively prohibited by the Convention and affirms the determination of States parties to condemn any use of biological agents or toxins other than for peaceful purposes, by anyone at any time."

Eighth Review Conference

The eighth BWC review conference took place in November 2016. At the end of the conference, delegates agreed to a future one-week meeting of states-parties at the end of the year and a five-year extension of the BWC Implementation Support Unit.

Ninth Review Conference

The ninth BWC review conference was repeatedly postponed due to the Covid-19 pandemic. It is scheduled to be held in August 2022.

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Chemical Weapons: Frequently Asked Questions

August 2020

Contact: Daryl Kimball, Executive Director, 202-463-8270 ext. 107; Kelsey Davenport, Director for Nonproliferation Policy, 202-463-8270 ext. 102.

Last Reviewed: January 2022

The use and possession of chemical weapons is prohibited under international law. However, several nations continue to maintain active chemical weapons programs, despite a prevailing norm against the use of chemical weapons and international efforts to destroy existing stockpiles.

The following are basic answers to frequently asked questions regarding the different types of chemical weapons and delivery systems, the history of chemical weapons use, international legal regimes that seek to curb the use and stockpiling of chemical weapons, and current efforts to verifiably destroy chemical weapons arsenals.

I. What are chemical weapons?
II. How are chemical weapons delivered?
III.  When have chemical weapons been used?
IV. Are chemical weapons prohibited?
V. What are riot control agents? What is the status of riot control agents under the CWC?
VI. Who has chemical weapons?
VII. How are chemical weapons destroyed?

I. What are chemical weapons?

A chemical weapon is any toxic chemical that can cause death, injury, incapacitation, and sensory irritation, deployed via a delivery system, such as an artillery shell, rocket, or ballistic missile. Chemical weapons are considered weapons of mass destruction and their use in armed conflict is a violation of international law.

Primary forms of chemical weapons include nerve agents, blister agents, choking agents, and blood agents. These agents are categorized based on how they affect the human body.

Nerve agents. Generally considered the most deadly of the different categories of chemical weapons, nerve agents – in liquid or gas form - can be inhaled or absorbed through the skin. Nerve agents inhibit the body’s respiratory and cardiovascular capability by causing severe damage to the central nervous system, and can result in death. The most common nerve agents include Sarin, Soman, and VX.

Blister agents. Blister agents can come in forms of gas, aerosol, or liquid and cause severe burns and blistering of the skin. They can also cause complications to the respiratory system if inhaled and digestive tract if ingested. Common forms of blister agents include Sulfur Mustard, Nitrogen Mustard, Lewisite and Phosgene Oximine.

Choking agents. Choking agents are chemical toxins that directly attack the body’s respiratory system when inhaled and cause respiratory failure. Common forms of choking agents include phosgene, chlorine, and chloropicrin.

Blood agents. Blood agents interfere with the body’s ability to use and transfer oxygen through the bloodstream. Blood agents are generally inhaled and then absorbed into the bloodstream. Common forms of blood agents include Hydrogen Chloride and Cyanogen Chloride.

Certain common industrial chemicals, such as chlorine, are not prohited under the 1997 Chemicals Weapons Convention, but if used as a weapon, such use is prohibited by the treaty.

Riot control agents, such as tear gas, are considered chemical weapons if used as a method of warfare. States can legitimately possess riot control agents and use them for domestic law enforcement purposes, but states that are members of the Chemical Weapons Convention must declare what type of riot agents they possess.

II. How are chemical weapons delivered?

A chemical weapon attack occurs in two phases: delivery and dissemination. The delivery phase refers to the launching of the rocket, bomb, or artillery shell. The dissemination phase involves the dispersal of the chemical agent from the weapon.

Chemical weapons can be delivered via a variety of mechanisms including but not limited to; ballistic missiles, air-dropped gravity bombs, rockets, artillery shells, aerosol canisters, land mines, and mortars.

Artillery shells are conventional shells that have been converted to disperse chemical weapons. The most traditional delivery vehicle of chemical agents, dispersion occurs through an explosive charge that expels the chemical agent laterally.

Air delivered systems can be deployed via gravity bombs, spray tanks, or rockets. Ground detonated and airburst gravity bombs are generally delivered through fixed-wing aircraft, while helicopters have been traditionally deployed with spray tanks and rockets.

Ballistic missiles carrying chemical weapons – via a fill tank or submunitions - utilize an airburst to disperse chemical agents over a broad area. The use of submunitions increases the area in which chemical agents can be dispersed. Compared to other delivery systems, ballistic missiles expand the range of targets that combatants can target with chemical weapons. However, the use of explosives to disperse the chemical agent reduces the potency of the weapon in combat situations.

Cruise missiles. Unlike ballistic missiles, which utilize explosives to discharge the agent, cruise missiles can disperse chemical agents in a gradual and controlled fashion.

Unmanned Aerial Vehicles or UAVs are another platform that combatants may utilize to disperse chemical agents. Like cruise missiles, UAVs are ideal platforms for slower dissemination due to controllable speeds, and dispersal over a wide area. UAVs can fly below radar detection and change directions, allowing them to be retargeted during flight.

Dissemination is the most critical phase of a chemical weapon and generally determines its effectiveness. Generally, dissemination has been done via explosives that expel the agent laterally. Other forms of dissemination include aerodynamic dissemination, a non-explosive delivery mechanism that deploys the chemical agent through dispersion lines.

III.  When have chemical weapons been used?

The use of harmful chemicals in warfare, personal attacks, and assassinations dates back centuries, but the rise of industrial production of chemicals in the late 19th century opened the door to the more massive use of chemical agents in combat. The first major use of chemicals on the battlefield was in World War I when Germany released chlorine gas from pressurized cylinders in April 1915 at Ypres, Belgium. Ironically, this attack did not technically violate the 1899 Hague Peace Conference Declaration, the first international attempt to limit chemical agents in warfare, which banned only “the use of projectiles the sole object of which is the diffusion of asphyxiating or deleterious gases.” Historians estimate that, with the introduction of mustard gases in 1917, chemical weapons and agents injured someone million soldiers and killed 100,000 during the 1914-1918 war.

The 1925 Geneva Protocol sought to ban the use of biological and chemical weapons, but many of its signers joined with major reservations. China, France, the Soviet Union, and the United Kingdom all joined in the 1920s, but Japan did not join until 1970 and the United States until 1975. Between the two world wars, there were a number of reports of the use of chemical weapons in regional conflicts: Morocco in 1923-1926, Tripolitania (Libya) in 1930, Sinkiang (China) in 1934, Abyssinia (Ethiopia) in 1935-1940, and Manchuria (China) in 1937-1942. World War II saw no major use of chemical weapons on the battlefield, with the exception of the Sino-Japanese conflict, and both President Franklin Roosevelt and German leader Adolf Hitler had stated publicly that they were personally against the first use of chemical weapons. Germany, however, did use deadly chemicals in the gas chambers of the Holocaust.

Most of the major powers in World War II developed, produced, and stockpiled large amounts of chemical weapons during the war. Since the end of the war in 1945, there have been only sporadic reports of limited use of chemical weapons, including in the Yemen war of 1963-1967 when Egypt bombed Yemeni villages, killing some 1,500 people. The United States heavily used herbicides such as Agent Orange and tear gas in the Vietnam War in the 1960s; although such chemicals are not covered under the Chemical Weapons Convention (CWC), some observers saw this as chemical warfare. Iraq used chemical weapons in the 1980-1988 Iran-Iraq war and against the Kurds in Halabja in 1988. These two cases provoked widespread public opposition to the horrors and indiscriminate nature of deadly chemical agents and certainly helped advance CWC negotiations, which had begun in the early 1980s, to their conclusion in 1992.

For more on the history of chemical weapons, use see “Abolishing Chemical Weapons: Progress, Challenges, and Opportunities” in November 2010 Arms Control Today.

The use of the nerve agent sarin by the Japanese terrorist group Aum Shinrikyo in June 1994 in Matsumoto, Japan, and again on March 20, 1995, in the Tokyo subway system, killing 19 people and injuring some 5,000, suddenly brought to light the potential threat of non-state actors intent on using weapons of mass destruction. The first official on-site inspection by the United States of a Russian chemical weapons stockpile in the Kurgan Oblast along the border of Kazakhstan in July 1994 illustrated that Russian chemical weapons arsenals left much to be desired regarding security against theft, diversion, and terrorism.

Iraqi insurgents in recent years have combined tanks of chlorine gas with improvised explosive devices, but with little success. There were reports of the possible limited use of chemical agents by Taliban insurgents in Afghanistan and by Turkish troops against Kurdish rebels in eastern Turkey, but these allegations remain unproven. In public statements, Osama bin Laden and al Qaeda threatened to use nuclear, chemical, biological, and radiological weapons.

In Syria, intelligence reports by the United States, the United Kingdom, and France assess that the Assad regime has used chemical weapons against opposition forces on numerous occasions since 2012, including an August 2013 attack in Ghouta, outside of Damascus, that killed more than 1,400 people. The UN-OPCW Joint Investigative Mechanism (JIM) has found the Syrian government responsible for numerous chemical weapons attacks, including in April 2014, March 2015, March 2016 and April 2017 and the Islamic State responsible for chemical weapons attacks in August 2015 and September 2016. The OPCW Investigation and Identification Team (IIT) also attributed a series of March 2017 chemical attacks to the Syrian Air Force. Reports of chemical weapons use in Syria continue to surface. For a complete timeline of Syrian chemical weapons use see Timeline of Syrian Chemical Weapons Activity, 2012-2020.

Kurdish and Iraqi military forces claim the Islamic State used chlorine gas in attacks in December 2014 and March 2015 in Iraq, but these accounts have not been verified by the OPCW.

In February 2017, North Korean agents used VX, a nerve agent, to assassinate Kim Jong-nam, the half-brother of North Korean leader Kim Jong-un in the airport in Kuala Lumpur, Malaysia.

In March 2018, the UK accused Russia of using a Novichok agent to assassinate a former Russian spy, Sergei Skripal, and his daughter, Yulia, in the UK.

IV. Are chemical weapons prohibited?

Yes. The horrendous and widespread use of chemical weapons in World War I prompted international efforts to curb the use and production of chemical agents.

The two major protocols that target chemical weapons are the 1925 Geneva Protocol and the Chemical Weapons Convention (CWC). The former provides the initial international legal framework for controls on the use of chemical weapons, while the latter establishes comprehensive international standards that ban the development, production, acquisition, stockpiling, use, transfer, or retention of chemical weapons for all CWC state parties.

1925 Geneva Protocol: Signed in 1925, the Geneva Protocol was drafted and signed at the Conference for the Supervision of the International Trade in Arms and Ammunition, and prohibits the use of chemical and biological weapons in the field of conflict. While it prohibits the use of chemical weapons, the Geneva Protocol does not regulate the production, research or stockpiling of these weapons. It allows nations to reserve the right to retaliate with chemical weapons should it be subject to an adversarial chemical attack. It also does not regulate the use of chemical weapons for internal conflicts. However, over time, through customary international law, it is widely considered applicable to these conflicts as well. Interest in verifiable elimination of existing stockpiles of chemical weapons fueled the push for the more robust CWC in 1993.

Chemical Weapons Convention: The Chemical Weapons Convention is a multilateral treaty that bans the development, production, acquisition, stockpiling, transfer, and use of chemical weapons and requires all possessor states to destroy their stockpiles safely. Opened for signature in Paris on January 13, 1993, the CWC entered into force in April 29, 1997, and has 193 members, including Palestine. Currently one nation– Israel– has signed but not ratified the treaty, while three nations (Egypt, North Korea, and South Sudan) have neither signed nor acceded to the CWC.

The CWC requires universal adherence to its protocols and establishes verification regimes that assure the destruction of member nations' chemical weapon stockpiles. The CWC requires member nations to declare all chemical weapons and chemical weapons sites, including research, development, and testing sites, to be subject to on-site inspection. According to Article VI of the treaty, destruction of a state party’s declared chemical weapons arsenal should begin no later than two years after the state joins the treaty and should finish no more than ten years after it has joined, although the treaty does allow a deadline extension of up to five years from that date. Verification is implemented through the Organization for the Prohibition of Chemical Weapons (OPCW), located in The Hague, Netherlands, and involves routine on-site inspections and reporting. The CWC also promotes multilateral cooperation on peaceful uses of chemistry and undertakes over 400 on-site inspections of the chemical industry annually.

For more information on the CWC, see Chemical Weapons Convention at a Glance.

V. What are riot control agents? What is the status of riot control agents under the CWC?

Riot control agents (RCAs) are chemical agents used both to control and disperse crowds and as personal protection. RCAs temporarily impede human function by irritating the eyes, mouth, throat, lungs, and skin. Prolonged exposure or exposure to a high concentration of an RCA can cause blindness, respiratory failure, or death.

The OPCW defines a chemical weapon as “a chemical used to cause intentional death or harm through its toxic properties.” In this respect, while the CWC does not overtly ban the production, stockpile, or use of RCAs, an RCA used as a method of warfare is prohibited by the CWC under this definition. States Parties agree under Article 1, Paragraph 5 of the Convention, “not to use riot control agents as a method of warfare.”

The Treaty permits use of RCAs by States for “domestic law enforcement purposes,” but requires States Parties to declare what RCAs they possess. Examples of common RCAs include Tear Gas (CS gas), Pepper Spray (OC), and Mace (CN).

In some states, groups are advocating for tightened restrictions on RCA use by domestic law enforcement, citing the prohibition of their use in warfare under the CWC, their indiscriminate nature, and the possible long-term health effects that exposure to them can cause.

VI. Who has chemical weapons?

Eight countries declared chemical weapons stockpiles when they joined the CWC: Albania, India, Iraq, Libya, Syria, the United States, Russia and an anonymous state widely believed to be South Korea. Of those eight countries, Albania, South Korea, India, Iraq, Syria, Libya and Russia have completed destruction of their declared arsenals. Syria, however, has not declared its entire stockpile. The United States plans to complete the destruction of its chemical weapons by September 2023.

When Russia, the United States, and Libya declared that they would be unable to meet their final destruction deadlines in 2012, CWC state parties agreed to extend the deadlines with increased national reporting and transparency.

Russia declared the largest stockpile with approximately 40,000 metric tons at seven arsenals in six regions of Russia. Russia's arsenal originally consisted of VX, sarin, soman, mustard, lewisite, mustard-lewisite mixtures, and phosgene.

Russia officially completed the destruction of its chemical weapons arsenal in 2017. Russia’s destruction program benefited from technical assistance and funding through the Cooperative Threat Reduction Program.

However, Russia still retains some chemical weapons capacity. In March 2018, Russia used the advanced chemical agent Novichok to assassinate a former Russian spy, Sergei Skripal, and his daughter Yulia, in the UK. In a 2021 State Department report on compliance with the CWC, the United States accused Russia of non-compliance with the CWC for its alleged use of Novichok. The report also noted that “The United States cannot certify that Russia has met its obligations" under the Convention and asserted that Russia had not made a complete declaration of its stockpile.

The United States declared 28,577 metric tons at nine stockpiles in eight states and on Johnston Atoll west of Hawaii. Albania and Libya declared the smallest stockpiles, with 16 and 23 metric tons respectively. India and South Korea declared stockpiles in the 500-1,000 metric ton range but maintained a high degree of secrecy around the size, location, composition, and destruction of their weapons.

Syria admitted that it had chemical weapons in July 2012. It joined the CWC on September 12, 2013, declaring its chemical weapons stockpile and determining a plan for its elimination soon after. The OPCW announced that the entirety of Syria’s declared stockpile of 1,308 metric tons of sulfur mustard agent and precursor chemicals had been destroyed by January 2016. The destruction processes were carried out on board the US Merchant Marine ship, Cape Ray, and in four countries – Finland, Germany, the United Kingdom, and the United States. However, reports continue to surface of chemical weapon use in Syria, raising questions about the accuracy of its initial declaration. In July 2020, the OPCW Executive Council adopted a resolution addressing the ongoing possession and use of chemical weapons by Syria. That resolution called on the Syrian government to declare the remainder of its chemical stockpile and to resolve any inconsistencies regarding its initial stockpile declaration within 100 days, or by mid-October, 2020. Thusfar, Syria has not done so.

North Korea, a non-signatory to the CWC, is widely reported to possess a large arsenal of chemical weapons, likely over 5,000 metric tons, including mustard, phosgene, and nerve agents. The use of VX nerve agent in the 2017 assassination in Kuala Lumpur strongly indicates that VX is part of North Korea’s chemical arsenal.

For more information, see Chemical and Biological Weapons Status at a Glance.

VII. How are chemical weapons destroyed?

The United States: The United States began construction of its first prototype incinerator on Johnston Atoll in the 1980s. In 1990, it began burning 1,842 metric tons of chemical weapons, which had been secretly shipped from forward deployment in Germany and Okinawa many years earlier. When the CWC entered into force in 1997, the United States was already operating its first two incinerators on Johnston Atoll and in Tooele, Utah, which was the largest U.S. chemical weapons stockpile with 12,353 metric tons. The U.S. Army burned 1,436 metric tons, about 5 percent of the total chemical stockpile, at the two sites before the April 1997 entry into force.

The U.S. Army initially planned to construct three centralized incinerators to destroy the U.S. chemical weapons stockpile, and early schedules optimistically showed the United States completing operations in 1994. Congress subsequently banned transportation of chemical munitions on safety and security grounds, necessitating the current plan for a destruction facility at each of the nine U.S. sites at which chemical weapons are stored.

When the U.S. Senate finally approved the CWC, on April 25, 1997, after a long and contentious debate, the articles of ratification specified, among many other conditions, that the president place the highest priority on protection of public health and the environment and that the Army undertake the development and demonstration of nonincineration technologies for chemical weapons destruction.

Today the United States has constructed and operated five large incinerators: on Johnston Atoll and in Tooele, Utah, as previously noted; in Umatilla, Oregon; in Anniston, Alabama; and in Pine Bluff, Arkansas. The Johnston Atoll incinerator finished operations in 2000; the other four completed operations in 2012. In addition, neutralization facilities were built in Newport, Indiana, and Edgewood, Maryland; they chemically treated and destroyed bulk VX nerve agent and mustard agent. The remaining two chemical weapons stockpiles in Pueblo, Colorado, and Blue Grass, Kentucky, will each be destroyed by chemical neutralization, followed by second-stage treatments of bioremediation and super-critical water oxidation (SCWO). The Pueblo facility began operations in 2016, and Blue Grass began shortly after, in June 2019.

In the OPCW’s annual report for 2018 it declared that the United States had destroyed approximately 90.6 percent - about 25,154 metric tons - of the chemical weapons stockpile it had declared as the CWC entered into force. The United States has destroyed all of Category 2 and Category 3 weapons. As of July 2020, the United States has 1,445.5 metric tons of mustard and nerve agents remaining in its stockpile. The United States is projected to complete destruction by September 2023.

Russia: Russian officials made it clear in 1997, when they ratified the CWC, that they would need technical and financial support from other CWC members to meet its treaty deadlines. During the 1994 U.S. visit to Russia, Russian military officials and the chairman of the Duma defense committee rejected a U.S. offer made by the assistant to the secretary of defense for nuclear, chemical, and biological defense programs to construct an incinerator at the Shchuch’ye chemical weapons stockpile. Russian officials wanted to determine their own technologies for demilitarization and were very wary of incineration as too complex, too expensive, too dangerous, and too politically contentious.

The first Russian chemical weapons demilitarization facility, built and funded as a prototype facility by Germany for neutralizing lewisite, an older, arsenic-based chemical agent, opened in 2002 at Gorny in the Saratov Oblast. Since then, Russia has been able to open five more destruction facilities, the last at Kizner in the Udmurt Republic.

Most of these facilities have been supported financially by the Global Partnership Against the Spread of Weapons and Materials of Mass Destruction, founded by the Group of Eight at its summit meeting in Kananaskis, Canada, in 2002. As of 2010, the United States through the Cooperative Threat Reduction (CTR or Nunn-Lugar) program committed more than $1 billion since the mid-1990s to the planning and construction of the neutralization facility at Shchuch’ye, while Germany has committed $475 million (340 million euros) to construction at Gorny, Kambarka, and Pochep. Canada and the United Kingdom have contributed some $82 million and $39 million, respectively, while at least another 10 additional countries have contributed some $25 million.

On September 27, 2017, the OPCW announced that Russia had completed the destruction of its chemical weapons arsenal.

Libya: Libya joined the CWC in 2004 and, in its submittal at the time, declared 23 metric tons of mustard agent in bulk containers. In addition, it declared one inactivated chemical weapons production facility, two chemical weapons storage sites, 1,300 metric tons of precursor chemicals, and 3,563 unfilled aerial bombs. It first planned on eliminating its chemical agent stockpile by the 2007 deadline.

However, after aborted attempts at U.S. and Italian partnerships in its demilitarization program, it asked for several OPCW deadline extensions. Destruction of the stockpile was halted in February 2011 due to the armed uprising that resulted in the overthrow of the Gaddafi regime. At that time, 11.5 metric tons of chemical weapons remained in Libya’s declared stockpiles.

Libya subsequently declared an additional chemical weapons stockpile and completed the destruction of its Category 1 chemical weapons in January 2014. With assistance from the OPCW and other member states including Canada and Denmark, Libya removed all of the remaining precursor chemicals from its territory for destruction in August 2016. The Syria case, which set the precedent for destroying chemical weapons outside of the country of origin, paved the way for shipping the remaining chemicals out of Libya for destruction in Germany. Libya completed the destruction of all its chemical weapons in January 2018.

For more information on the destruction of Libya’s chemical weapons see Chronology of Libya’s Disarmament and Relations with the United States.

Iraq: Iraq joined the CWC in early 2009 and declared two large, sealed "Al Muthana" bunkers in the Fallujah region with chemical weapons and related equipment and debris from the 1991 Persian Gulf War. Because at least one of these bunkers had been hit by aerial bombs in the war, there is no final inventory of weapons and agents, nor a thorough evaluation of the possible risks of open agents or unexploded ordnance in the bunkers. The OPCW declared Iraq's destruction complete in March 2018.

Albania: Albania was the first possessor state to destroy its stockpile. Although it joined the CWC in 1994, it did not acknowledge its possession of 16 metric tons of mustard agent (as well as small quantities of lewisite and other chemicals) until 2003. The OPCW declared Albania’s destruction complete in July 2007.

South Korea: South Korea refused to acknowledge its stockpile in any public presentations, including the annual speeches by its ambassador to the OPCW, and has claimed full confidentiality (“highly protected information”) under the Confidentiality Annex of the CWC; all OPCW delegations and staff therefore refer to it as “A State Party” in reference to declared possessor states. South Korea completed the destruction of its chemical weapons in 2008.

India: India declared a stockpile of 1,044 tons of sulfur mustard in 1997 after ratifying the CWC in 1996. India completed the destruction of its entire chemical weapons stockpile in 2009.

-Research Assistance by Julia Masterson

Strategic Arms Control and Policy

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Chemical Weapons Convention Signatories and States-Parties

June 2018 

Contact: Daryl KimballExecutive Director, (202) 463-8270 x107

The Chemical Weapons Convention (CWC) entered into force on April 29, 1997, and currently has 193 states-parties. One state has signed but not ratified (Israel). Three states have neither signed nor ratified (Egypt, North Korea, and South Sudan).

For a guide to the convention, see The Chemical Weapons Convention (CWC) at a Glance.

Country Signature Ratification/Accession
Afghanistan 1/14/93 9/24/03
Albania 1/14/93 5/11/94
Algeria 1/13/93 8/14/95
Andorra 2/27/03
Angola 9/16/15
Antigua & Barbuda 8/29/05
Argentina 1/13/93 10/2/95
Armenia 3/19/93 1/27/95
Australia 1/13/93 5/6/94
Austria 1/13/93 8/17/95
Azerbaijan 1/13/93 2/29/00
Bahamas 3/2/94 4/21/09
Bahrain 2/24/93 4/28/97
Bangladesh 1/14/93 4/25/97
Barbados 3/7/07
Belarus 1/14/93 7/11/96
Belgium 1/13/93 1/27/97
Belize 12/1/03
Benin 1/14/93 5/14/98
Bhutan 4/23/97 8/18/05
Bolivia 1/14/93 8/14/98
Bosnia and Herzegovina 1/16/97 2/25/97
Botswana 8/31/98
Brazil 1/13/93 3/13/96
Brunei Darussalem 1/13/93 7/28/97
Bulgaria 1/13/93 8/10/94
Burkina Faso 1/14/93 7/8/97
Burundi 1/15/93 9/4/98
Cambodia 1/15/93 7/19/05
Cameroon 1/14/93 9/16/96
Canada 1/13/93 9/26/95
Cape Verde 1/15/93 10/10/03
Central African Republic 1/14/93 9/20/06
Chad 10/11/94 2/13/04
Chile 1/14/93 7/12/96
China 1/13/93 4/25/97
Colombia 1/13/93 4/5/00
Comoros 1/13/93 9/17/06
Congo 1/15/93 12/4/07
Cook Islands 1/14/93 7/15/94
Costa Rica 1/14/93 5/31/96
Côte d'Ivoire 1/13/93 12/18/95
Croatia 1/13/93 5/23/95
Cuba 1/13/93 4/29/97
Cyprus 1/13/93 8/28/98
Czech Republic 1/14/93 3/6/96
Democratic Republic of Congo 1/14/93 10/12/05
Denmark 1/14/93 7/13/95
Djibouti 9/28/93 1/25/06
Dominica 8/2/93 2/12/01
Dominican Republic 1/13/93 3/26/09
Ecuador 1/14/93 9/6/95
El Salvador 1/14/93 10/30/95
Equatorial Guinea 1/14/93 4/25/97
Eritrea 2/14/00
Estonia 1/14/93 5/26/99
Ethiopia 1/14/93 5/13/96
Fiji 1/14/93 1/20/93
Finland 1/14/93 2/7/95
France 1/13/93 3/2/95
Gabon 1/13/93 9/8/00
Gambia 1/13/93 5/19/98
Georgia 1/14/93 11/27/95
Germany 1/13/93 8/12/94
Ghana 1/14/93 7/9/97
Greece 1/13/93 12/22/94
Grenada 4/9/97 6/3/05
Guatemala 1/14/93 2/12/03
Guinea 1/14/93 6/9/97
Guinea-Bissau 1/14/93 6/19/08
Guyana 10/6/93 9/12/97
Haiti 1/14/93 2/22/06
Holy See 1/14/93 5/12/99
Honduras 1/13/93 8/29/05
Hungary 1/13/93 10/31/96
Iceland 1/13/93 4/28/97
India 1/14/93 9/3/96
Indonesia 1/13/93 11/12/98
Iran 1/13/93 11/3/97
Iraq 1/13/09
Ireland 1/14/93 6/24/96
Israel 1/13/93
Italy 1/13/93 12/8/95
Jamaica 4/18/97 9/8/00
Japan 1/13/93 9/15/95
Jordan 10/29/97
Kazakhstan 1/14/93 3/23/00
Kenya 1/15/93 4/25/97
Kiribati 9/7/00
Kuwait 1/27/93 5/28/97
Kyrgyzstan 2/22/93 9/29/03
Laos 5/13/93 2/25/97
Latvia 5/6/93 7/23/96
Lebanon 11/20/08
Lesotho 12/7/94 12/7/94
Liberia 1/15/93 3/25/06
Libya 1/6/04
Liechtenstein 7/21/93 11/24/99
Lithuania 1/13/93 4/15/98
Luxembourg 1/13/93 4/15/97
Macedonia 6/20/97
Madagascar 1/15/93 10/20/04
Malawi 1/14/93 6/11/98
Malaysia 1/13/93 4/20/00
Maldives 10/1/93 5/31/94
Mali 1/13/93 4/28/97
Malta 1/13/93 4/28/97
Marshall Islands 1/13/93 5/19/04
Mauritania 1/13/93 2/9/98
Mauritius 1/14/93 2/9/93
Mexico 1/13/93 8/29/94
Micronesia 1/13/93 6/21/99
Moldova 1/13/93 7/8/96
Monaco 1/13/93 6/1/95
Mongolia 1/14/93 1/17/95
Montenegro 10/23/06
Morocco 1/13/93 12/28/95
Mozambique 8/15/00
Myanmar 1/14/93 08/07/15
Namibia 1/13/93 11/27/95
Nauru 1/13/93 11/12/01
Nepal 1/19/93 11/18/97
Netherlands 1/14/93 6/30/95
New Zealand 1/14/93 7/15/96
Nicaragua 3/9/93 11/5/99
Niger 1/14/93 4/9/97
Nigeria 1/13/93 5/20/99
Niue 4/21/05
North Korea    
Norway 1/13/93 4/7/94
Oman 2/2/93 2/8/95
Pakistan 1/13/93 10/28/97
Palau 2/3/03
Palestine 5/17/18
Panama 6/16/93 10/7/98
Papua New Guinea 1/14/93 4/17/96
Paraguay 1/14/93 12/1/94
Peru 1/14/93 7/20/95
Philippines 1/13/93 12/11/96
Poland 1/13/93 8/23/95
Portugal 1/13/93 9/10/96
Qatar 2/1/93 9/3/97
Romania 1/13/93 2/15/95
Russia 1/13/93 11/5/97
Rwanda 5/17/93 3/31/04
St. Kitts & Nevis 3/16/94 5/21/04
St. Lucia 3/29/93 4/9/97
St. Vincent & the Grenadines 9/20/93 9/18/02
Samoa 1/14/93 9/27/02
San Marino 1/13/93 12/10/99
Sao Tome and Principe 9/9/03
Saudi Arabia 1/20/93 8/9/96
Senegal 1/13/93 7/20/98
Serbia 4/20/00
Seychelles 1/15/93 4/7/93
Sierra Leone 1/15/93 9/30/04
Singapore 1/14/93 5/21/97
Slovak Republic 1/14/93 10/27/95
Slovenia 1/14/93 6/11/97
Solomon Islands 9/23/04
Somalia 5/29/13
South Africa 1/14/93 9/13/95
South Korea 1/14/93 4/28/97
South Sudan    
Spain 1/13/93 8/3/94
Sri Lanka 1/14/93 8/19/94
Sudan 5/24/99
Suriname 4/28/97 4/28/97
Swaziland 9/23/93 11/20/96
Sweden 1/13/93 6/17/93
Switzerland 1/14/93 3/10/95
Syria   9/12/13*
Tajikistan 1/14/93 1/11/95
Tanzania 2/25/94 6/25/98
Thailand 1/14/93 12/10/02
Timor Leste 5/7/03
Togo 1/13/93 4/23/97
Tonga 5/29/03
Trinidad & Tobago 6/24/97
Tunisia 1/13/93 4/15/97
Turkey 1/14/93 5/12/97
Turkmenistan 10/12/93 9/29/94
Tuvalu 1/19/04
Uganda 1/14/93 11/30/01
Ukraine 1/13/93 10/16/98
United Arab Emirates 2/2/93 11/28/00
United Kingdom 1/13/93 5/13/96
United States 1/13/93 4/25/97
Uruguay 1/15/93 10/6/94
Uzbekistan 11/24/95 7/23/96
Vanuatu 9/16/05
Venezuela 1/14/93 12/3/97
Vietnam 1/13/93 9/30/98
Yemen 2/8/93 10/2/00
Zambia 1/13/93 2/9/01
Zimbabwe 1/13/93 4/25/97

*Syria sent a letter to the United Nations Secretary-General which said that Assad signed a legislative decree providing the accession of Syria to the Chemical Weapons Convention. In the letter, Assad said Syria would observe its CWC obligations immediately, as opposed to 30 days from the date of accession, as stipulated in the treaty.

    Source: Organization for the Prohibition of Chemical Weapons

    Chemical/Biological Arms Control

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    The Chemical Weapons Convention (CWC) at a Glance

    April 2020

    Contact: Daryl G. Kimball, Executive Director, 202-463-8270 x 107

    The Chemical Weapons Convention (CWC) is a multilateral treaty that bans chemical weapons and requires their destruction within a specified period of time. The treaty is of unlimited duration and is far more comprehensive than the 1925 Geneva Protocol, which outlaws the use but not the possession of chemical weapons.

    CWC negotiations started in 1980 in the UN Conference on Disarmament.  The convention opened for signature on January 13, 1993, and entered into force on April 29, 1997.

    The CWC is implemented by the Organization for the Prohibition of Chemical Weapons (OPCW), which is headquartered in The Hague with about 500 employees. The OPCW receives states-parties’ declarations detailing chemical weapons-related activities or materials and relevant industrial activities. After receiving declarations, the OPCW inspects and monitors states-parties’ facilities and activities that are relevant to the convention, to ensure compliance.

    The CWC is open to all nations and currently has 193 states-parties. Israel has signed but has yet to ratify the convention. Three states have neither signed nor ratified the convention (Egypt, North Korea and South Sudan).


    The Chemical Weapons Convention prohibits:

    • Developing, producing, acquiring, stockpiling, or retaining chemical weapons.
    • The direct or indirect transfer of chemical weapons.
    • Chemical weapons use or military preparation for use.
    • Assisting, encouraging, or inducing other states to engage in CWC-prohibited activity.
    • The use of riot control agents “as a method of warfare.”

    Declaration Requirements

    The CWC requires states-parties to declare in writing to the OPCW their chemical weapons stockpiles, chemical weapons production facilities (CWPFs), relevant chemical industry facilities, and other weapons-related information. This must be done within 30 days of the convention's entry into force for each member state.

    Chemical Weapons Stockpiles—States-parties must declare all chemical weapons stockpiles, which are broken down into three categories:

    • Category 1: chemical weapons based on Schedule 1 chemicals, including VX and sarin. (See below for an explanation of “scheduled” chemicals.)
    • Category 2: chemical weapons based on non-Schedule 1 chemicals, such as phosgene.
    • Category 3: chemical weapons including unfilled munitions, devices and equipment designed specifically to employ chemical weapons.

    Other weapons-related declarations states-parties must make include:

    • Chemical weapons production facilities on their territories since January 1, 1946.
    • Facilities (such as laboratories and test sites) designed, constructed, or used primarily for chemical weapons development since January 1, 1946.
    • “Old” chemical weapons on their territories (chemical weapons manufactured before 1925 or those produced between 1925 and 1946 that have deteriorated to such an extent that they are no longer useable).
    • “Abandoned” chemical weapons (abandoned by another state without consent on or after January 1, 1925).
    • Plans for destroying weapons and facilities.
    • All transfers or receipts of chemical weapons or chemical weapons-production equipment since January 1, 1946.
    • All riot control agents in their possession.

    Chemical Industry—The CWC requires states-parties to declare chemical industry facilities that produce or use chemicals of concern to the convention. These chemicals are grouped into “schedules,” based on the risk they pose to the convention. A facility producing a Schedule 1 chemical is considered a Schedule 1 facility.

    • Schedule 1 chemicals and precursors pose a “high risk” to the convention and are rarely used for peaceful purposes. States-parties may not retain these chemicals except in small quantities for research, medical, pharmaceutical, or defensive use. Many Schedule 1 chemicals have been stockpiled as chemical weapons.
    • Schedule 2 chemicals are toxic chemicals that pose a “significant risk” to the convention and are precursors to the production of Schedule 1 or Schedule 2 chemicals. These chemicals are not produced in large quantities for commercial or other peaceful purposes.
    • Schedule 3 chemicals are usually produced in large quantities for purposes not prohibited by the CWC but still pose a risk to the convention. Some of these chemicals have been stockpiled as chemical weapons.

    The CWC also requires the declaration of facilities that produce certain nonscheduled chemicals.

    Destruction Requirements

    The convention requires states-parties to destroy:

    • All chemical weapons under their jurisdiction or control.
    • All chemical weapons production facilities under their jurisdiction or control.
    • Chemical weapons abandoned on other states’ territories.
    • Old chemical weapons.

    Category 1 chemical weapons destruction must start within two years after the CWC enters into force for a state-party. States-parties must destroy 1 percent within three years of the CWC's entry into force, 20 percent within five years, 45 percent within seven years, and 100 percent within 10 years. States parties that signed the treaty when it entered into force in 1997 were supposed to complete destruction of category 1 chemicals by April 29, 2007.

    States-parties that signed the treaty when it entered into force were supposed to destroy their entire stockpiles by April 29, 2012. However, the OPCW may extend these deadlines due to “exceptional circumstances,” and in December 2006, the OPCW Executive Council granted nearly all possessors extensions of differing lengths. The only exception was Albania, which was the sole state-party nearing the complete destruction of its stockpile at that time,

    Category 2 and 3 chemical weapons destruction must start within one year after the CWC enters into force for a state-party.

    Destruction of CWPFs capable of producing Schedule 1 chemicals must start within one year after the CWC enters into force for a state-party. States-parties that signed the treaty when it originally entered into force had to complete of CWPFs producing schedule 1 chemicals by April 29, 2007.

    Destruction of other CWPFs must start within one year after the CWC enters into force for a state-party. States-parties that signed the treaty when it originally entered into force had to complete destruction by April 29, 2002.

    States-parties may request to convert CWPFs to facilities that they can use for nonprohibited purposes. Once their requests are approved, states-parties that signed the treaty when it originally entered into force were supposed to complete conversion by April 29, 2003.

    On-Site Activity

    The convention establishes three types of on-site activities that aim to generate confidence in states-parties’ CWC compliance. These include:

    • “Routine inspections” of chemical weapons-related facilities and chemical industry facilities to verify the content of declarations and to confirm that activities are consistent with CWC obligations.
    • “Challenge inspections” which can be conducted at any facility or location in states-parties to clarify questions of possible noncompliance. (To prevent abuse of this measure, the OPCW’s executive body can vote by a three-quarters majority to stop a challenge inspection from going forward.)
    • Investigations of alleged use of chemical weapons.


    The convention encourages trade among states-parties, calling upon them not to maintain restrictions on one another that would hamper the trade of chemical-related items to be used for peaceful purposes. The convention does restrict trade with non-states-parties, outlawing the transfer of Schedule 1 and 2 chemicals.  To ensure that Schedule 3 transfers to non-states-parties are not used for purposes prohibited by the convention, the CWC requires exporting states-parties to obtain an end-use certificate from importing states.

    Penalties for Noncompliance

    If states-parties are found to have engaged in prohibited actions that could result in “serious damage” to the convention, the OPCW could recommend collective punitive measures to other states-parties. In cases of “particular gravity,” the OPCW could bring the issue before the UN Security Council and General Assembly.

    States-parties must take measures to address questions raised about their compliance with the CWC. If they do not, the OPCW may, inter alia, restrict or suspend their CWC-related rights and privileges (such as voting and trade rights).

    Sources: Arms Control Association, OPCW (http://www.opcw.org/news-publications/publications/facts-and-figures/)

    Possessor States' Category I Destruction Implementation


    Declared Category 1 Stockpile

    Declared Agents

    Remaining Stockpile



    16 metric tons



    Completed destruction on July 11, 2007.


    1,044 metric tons

    Sulfur Mustard


    Completed destruction on March 16, 2009


    Unknown Quantity



    The OPCW announced the destruction of Iraq's chemical weapons remnants on March 13, 2018.


    24.7 metric tons1

    Sulfur Mustard


    Completed destruction of Category 1 chemicals on May 4, 2013


    40,000 metric tons

    Lewisite, Mustard, Phosgene, Sarin, Soman, VX


    Completed destruction on September 27, 2017.

    South Korea

    605 metric tons



    Completed destruction on July 10, 2008.


    1,308 metric tons

    Sulfur Mustard

    Declared stockpile has been eliminated but undeclared chemicals still exist

    No projected timeline for destruction of undecared chemicals.

    United States

    27,771 metric tons

    Binary nerve agents, Lewisite, Mustard, Sarin, Soman, VX

    1,731.8 metric tons (as of March 27, 2020)

    Will not meet deadline; U.S. estimates September, 2023.

    1. Libya's official 2004 declaration was 24.7 metric tons. Libya declared additional CW stocks in November 2011 and February 2012, bringing the total to 26.3 metric tons.

    Chemical/Biological Arms Control

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    Chemical and Biological Weapons Status at a Glance

    March 2022

    Despite the progress made by international conventions, biological weapons (BW) and chemical weapons (CW) still pose a threat.

    More progress has been made by Chemical Weapons Convention (CWC) states-parties and the Organization for the Prohibition of Chemical Weapons (OPCW) in the destruction of declared CW stockpiles. Progress on the implementation of the Biological Weapons Convention (BWC), however, has been slower due to the lack of a formal verification mechanism.

    There are 183 States Parties to the BWC, including Palestine, and four signatories (Egypt, Haiti, Somalia, and Syria). Ten states have neither signed nor ratified the BWC (Chad, Comoros, Djibouti, Eritrea, Israel, Kiribati, Micronesia, Namibia, South Sudan and Tuvalu).

    For more information about the BWC, please see BWC at a Glance.

    There are 193 states parties to the Chemical Weapons Convention. Israel has signed but not ratified the convention and Egypt, North Korea, South Sudan have neither signed nor ratified the CWC.

    For more information about the CWC, please see CWC at a Glance and Chemical Weapons: Frequently Asked Questions.

    Below is a list of states believed to currently possess or have once possessed biological and/or chemical weapons and their current status. Some states have officially declared BW or CW programs, while other programs have been alleged to exist by other states. Therefore, both official declarations and unofficial allegations of chemical and biological weapons programs are included below.


    State declaration: Although it joined the CWC in 1994, Albania did not acknowledge its possession of 16 metric tons of mustard agent (as well as small quantities of lewisite and other chemicals) until 2003. The OPCW declared Albania’s destruction complete in July 2007.


    State Declaration: China states that it is in compliance with its BWC obligations and that it has never had an active BW program.

    Allegations: According to the United States, China’s BW activities have been extensive, and a 1993 State Department Compliance Report alleged that activities continued after China joined the BWC. The 2021 State Department Report on Compliance with Arms Control, Nonproliferation, and Disarmament Agreements and Commitments indicates that China is engaged in biological research with “potential dual-use applications.” According to the report, “the United States does not have sufficient information to determine whether China eliminated its assessed biological warfare (BW) program.”

    State Declaration: China states that it is in compliance with the CWC. China declared in 1997 that it had a small offensive CW program that has now been dismantled, which has been verified by over 400 inspections by the OPCW as of 2016.

    Allegations: The U.S. alleged in 2003 that China has an “advanced chemical weapons research and development program.” However, these allegations have decreased in magnitude in recent years and the State Department’s 2019 report on compliance with the CWC cited no such concerns.

    Other Information: Approximately 350,000 chemical munitions were left on Chinese soil by Japan during the Second World War. Work with Japan to dispose of these is ongoing.


    State declaration: Cuba denies any BW research efforts.

    Allegations: A 2003 State Department Compliance Report indicated that Cuba had “at least a limited developmental offensive biological warfare research and development effort.” The 2010 report claimed that “available information did not indicate Cuba’s dual-use activities during the reporting period involved activities prohibited by the BWC.” The 2017 report did not mention any problems with Cuba’s compliance with BWC.

    Allegations of BW programs have been made by Cuban defectors in the past.

    Other information: Cuba has a relatively advanced biotechnology industrial capabilities.


    State declaration: A vague statement alluding to a BW capability was reportedly made by President al-Sadat in 1970, but Egypt has not officially declared a biological weapons stockpile.

    Allegations: There have been various allegations that Egypt possesses biological weapons. Some argue that Egypt’s reluctance to ratify the BWC signals that it does possess biological weapons. The United States alleged that Egypt had developed a biological weapons stockpile by 1972. The 2014 State Department compliance report notes that Egypt has "continued to improve its biotechnology infrastructure" over the past three years, including through research and development activities involving genetic engineering, as of 2013's end, "available information did not indicate that Egypt is engaged in activities prohibited by the BWC."

    Allegations: There is strong evidence that Egypt employed bombs and artillery shells filled with phosgene and mustard agents during the Yemen Civil War from (1963 – 1967) but it is unclear if Egypt currently possesses chemical weapons. In 1989, the United States and Switzerland alleged that Egypt was producing chemical weapons in a plant north of Cairo. As a non-party to the CWC, Egypt has not had to issue any formal declarations about CW programs and capabilities.


    State declaration: India declared in June 1997 that it possessed a CW stockpile of 1,044 metric tons of mustard agent. India completed destruction of its stockpile in 2009.


    State declaration: Iran has publicly denounced BW.

    Allegations: The Defense Intelligence Agency alleged in 2009 that Iran’s BW efforts “may have evolved beyond agent R&D, and we believe Iran likely has the capability to produce small quantities of BW agents but may only have a limited ability to weaponize them.” In the 2021 compliance report, the United States alleged that “Iran has not abandoned its intention to conduct research and development of biological agents and toxins for offensive purposes.” 

    State declaration: Iran has denounced the possession and use of CW in international forums.

    Allegations: Pre-2003 U.S. intelligence assessments alleged that Iran had a stockpile of CW. This stockpile is thought to have included blister, blood, and choking agents and probably nerve agents. The United States accused Iran in 2021 of non-compliance with the CWC for an incomplete stockpile and facilities declaration and alleged concern that Iran may be pursuing pharmaceutical-based agents for a military purpose.

    Other information: Iran suffered tens of thousands of casualties from Iraqi use of chemical weapons during the1980-1988 Iran-Iraq war. Iran’s CW program is believed to have been started after Iraqi CW use. There are no known credible allegations that Iran used any chemical weapons against Iraq in response.


    State declaration: Iraq admitted to testing and stockpiling BW in the mid-1990s. These stockpiles appear to have been destroyed prior to the 2003 invasion. There have been no declarations about BW after 2003.

    State declaration: Iraq had an extensive chemical weapons program before the Persian Gulf War dating back to the 1960s under which it produced and stockpiled mustard, tabun, sarin, and VX. Iraq delivered chemical agents against Iranian forces during the Iran-Iraq War using aerial bombs, artillery, rocket launchers, tactical rockets, and helicopter-mounted sprayers and it also used chemical weapons against its Kurdish population in 1988. Its program was largely dismantled by United Nations weapons inspectors in the 1990s.

    Iraq declared in August 1998 that it had dismantled all of its chemical weapons in partnership with the UN Special Commission established for that purpose.

    Iraq then submitted an additional declaration to the OPCW of an unknown quantity of chemical weapons remnants contained in two storage bunkers in March 2009. Destruction activities were delayed due to an unstable security situation, but began in 2017. On March 13, 2018, the OPCW announced that all of Iraq's chemical weapons had been destroyed.


    State declaration: Israel has revealed little in terms of its biological weapons capabilities or programs.

    Allegations: There is belief that Israel has had an offensive BW program in the past. It is unclear if this is still the case.

    Allegations: Some allege that Israel had an offensive CW program in the past. It is unclear if Israel maintains an ongoing program.


    State declaration: Libya announced in December 2003 that it would eliminate its BW program.

    Allegations: Between 1982 and 2003 there were many allegations of a Libyan biological weapons program, although later inspections failed to reveal any evidence to support these claims.

    State declaration: In 2003, Libya announced it would be abandoning its CW program and in 2004 it declared possession of chemical agents and facilities. Libya declared 24.7 metric tons of mustard agent in bulk containers. In addition, it declared one inactivated chemical weapons production facility, two chemical weapons storage sites, 1,300 metric tons of precursor chemicals, and 3,563 unfilled aerial bombs. Libya completed the destruction of its Category 1 chemical weapons in January 2014. With assistance from the OPCW and other member states, Libya removed all of the remaining chemical weapons from its territory for destruction in August 2016. In January 2018, the OPCW declared that Libya's entire chemical weapons arsenal had been destroyed.

    For more information on Libya's disarmament see Chronology of Libya's Disarmament and Relations with the United States.


    Allegations: In a 2012 Ministry of National Defense White Paper,  South Korea asserted that “North Korea likely has the capability to produce[…] anthrax, smallpox, pest, francisella tularensis, and hemorrhagic fever viruses.” The United States assessed North Korea to be in noncompliance with the BWC in its 2021 compliance report

    Allegations: North Korea is widely believed to possess a large chemical stockpile including nerve, blister, choking, and blood agents. The 2012 unclassified intelligence assessment provided to Congress states that North Korea has a "long standing CW program" and "possesses a large stockpile of agents." In February 2017, North Korean agents used VX, a nerve agent, to assassinate Kim Jong Nam, the half-brother of Kim Jong Un in Malaysia.


    State declaration: In January 1992, Boris Yeltsin acknowledged that the Soviet Union had pursued an extensive and offensive BW program throughout the 1970s and 1980s. However, since joining the BWC in 1992, Russia has repeatedly expressed its commitment to the destruction of its biological weapons.

    Allegations: The Soviet Union’s extensive offensive germ program included weaponized tularemia, typhus, Q fever, smallpox, plague, anthrax, Venezuelan equine encephalitis, glanders, brucellosis, and Marburg. The Soviet Union also researched numerous other agents and toxins that can attack humans, plants, and livestock.

    The United States has repeatedly expressed concern about Russia’s inherited biological weapons program and uncertainty about Russia’s compliance with the BWC.

    The 2010 State Department report on compliance with the BWC details that Russia continues to engage in dual-use biological research activities, yet there is no evidence that such work is inconsistent with BWC obligations. It assesses that it remains unclear whether Russia has fulfilled its obligations under Article I of the convention. The 2017 report states that “Russia’s annual BWC CBM submissions since 1992 have not satisfactorily documented whether the BW items under these programs were destroyed or diverted to peaceful purposes, as required by Article II of the BWC.”

    In its 2021 compliance report, the United States concluded that “the Russian Federation maintains an offensive BW program and is in violation of its obligations under Articles I and II of the BWC.”

    State declaration: Russia possessed the world’s largest chemical weapons stockpile: approximately 40,000 metric tons of chemical agent, including VX, sarin, soman, mustard, lewisite, mustard-lewisite mixtures, and phosgene.

    Russia has declared its arsenal to the OPCW and commenced destruction. Along with the United States, Russia received an extension when it was unable to complete destruction by the 2012 deadline imposed by the CWC. A 2016 OPCW report indicated that as of 2015, Russia had destroyed about 92 percent of its stockpile (around 36,7500 metric tons). On September 27, 2017, the OPCW announced that Russia completed destruction of its chemical weapons arsenal.

    Allegations: The UK accused Russia of assassinating a former Russian spy, Sergei Skripal, and his daughter Yulia, in the UK using the chemical agent Novichok on March 4, 2018. In a 2021 State Department report on compliance with the CWC, the United States accused Russia of non-compliance with the CWC for its alleged use of Novichok. The report also noted that “The United States cannot certify that Russia has met its obligations" under the Convention, and asserted that Russia had not made a complete declaration of its stockpile.


    State declaration: South Korea declared a chemical weapons stockpile of unspecified agents when it joined the CWC in 1997 and completed destruction of its declared arsenal on July 10, 2008. It does not admit publically that it possessed chemical weapons and was noted in OPCW materials as a “state party.”


    State declaration: After acceding to the CWC in 1999, Sudan declared only a small selection of unspecified riot control agents.

    Allegations: There are unconfirmed reports that Sudan developed and used CW in the past. The U.S. bombed an alleged CW factory in 1998. There have been no serious allegations in recent years. Sudan was not included in the 2017 State Department report on compliance with the CWC.


    State declaration: In July 2012, a spokesman for the Syrian Foreign Ministry confirmed that the country possesses biological warfare materials, but little is known about the extent of the arsenal. On July 14, 2014, Syria declared the existence of production facilities and stockpiles of purified ricin, although little is known about the continued existence of such facilities in 2017.

    State declaration: On September 20, 2013, Syria submitted a declaration of its chemical weapons and facilities to the OPCW after years of denying the program's existence. The OPCW announced that the entirety of Syria’s declared stockpile of 1,308 metric tons of sulfur mustard agent and precursor chemicals had been destroyed in January 2016. However, reports continue to surface of chemical weapon use in Syria, raising questions about the accuracy of its initial declaration.

    Allegations: Syria had an extensive program producing a variety of agents, including nerve agents such as sarin and VX, and blistering agents, according to governments and media sources. There were also some allegations of deployed CWs on SCUD missiles. Several UN-OPCW Joint Investigative Mechanism (JIM) reports have found that the Syrian government was responsible for chemical weapons attacks in Syria, including in April 2014, March 2015, March 2016, and April 2017 and that the Islamic State was responsible for chemical weapons attacks in Syria in August 2015 and September 2016. In the 2019 State Department report on CWC compliance, the United States alleged that Syrian chemical weapons were also used in 2018.

    The United States continues to certify Syria in noncompliance with the CWC, most recently in the 2021 Report on CWC compliance.

    For more information about Syrian chemical weapon use see Timeline of Syrian Chemical Weapons Activity, 2012-2018.


    State declaration: Taiwan has declared that it possesses small quantities of CW for research but denies any weapons possession.


    State declaration: The United States unilaterally gave up its biological weapons program in 1969. The destruction of all offensive BW agents occurred between 1971 and 1973. The United States currently conducts research as part of its biodefense program.

    Allegations: According to a compliance report published by the Russian government in August 2010, the United States is undertaking research on Smallpox which is prohibited by the World Health Organization. Russia also accused the United States of undertaking BW research in order to improve defenses against bio-terror attacks which is “especially questionable from the standpoint of Article I of the BTWC.”

    State declaration: The United States declared a large chemical arsenal of 27,770 metric tons to the OPCW after the CWC came into force in 1997. Along with Russia, the United States received an extension when it was unable to complete destruction of its chemical stockpiles by 2012. . A 2019 OPCW report declared that the United States had destroyed approximately 91.47 percent of the chemical weapons stockpile it had declared as the CWC entered into force; over 25,000 metric tons of the declared total of 27,770. The United States has destroyed all of Category 2 and Category 3 weapons and is projected to complete destruction of its Category 1 weapons by September 2023.

    Allegations: The Russian government has accused the United States on multiple occasions of violating its commitments to the BWC, including by alleging in a 2010 compliance report that the United States undertook research on Smallpox, which is prohibited by the World Health Organization. Russia also accused the United States in 2018 of undertaking BW research at a series of U.S.-funded labs near Russia and China, specifically at the Richard G. Lugar Center for Public Health Research in Tbilisi, Georgia – an allegation which the U.S. Department of Defense denied.

    Chemical/Biological Arms Control

    Fact Sheet Categories:

    Chronology of Libya's Disarmament and Relations with the United States

    March 2021

    Contact: Kelsey Davenport, Director for Nonproliferation Policy, (202) 463-8270 x102

    Updated: January 2018

    On December 19, 2003, long-time Libyan President Muammar Gaddafi stunned much of the world by renouncing Tripoli’s weapons of mass destruction (WMD) programs and welcoming international inspectors to verify that Tripoli would follow through on its commitment.

    Following Gaddafi’s announcement, inspectors from the United States, United Kingdom, and international organizations worked to dismantle Libya’s chemical and nuclear weapons programs, as well as its longest-range ballistic missiles. Washington also took steps toward normalizing its bilateral relations with Tripoli, which had essentially been cut off in 1981.

    Libya’s decision has since been characterized as a model for other states suspected of developing WMD in noncompliance with their international obligations to follow. Assistant Secretary of State for Arms Control Stephen Rademaker stated May 2, 2005 during the nuclear Nonproliferation Treaty (NPT) Review Conference that Libya’s choice “demonstrates that, in a world of strong nonproliferation norms, it is never too late to make the decision to become a fully compliant NPT state,” noting that Tripoli’s decision has been “amply rewarded.”

    Tripoli’s disarmament was also a success story for the U.S. intelligence community, which uncovered and halted some of the assistance Libya was being provided by the nuclear smuggling network led by Pakistani nuclear official Abdul Qadeer Khan. At  that time, the U.S. intelligence community was being harshly criticized for its failures regarding Iraq’s suspected WMD programs.

    The factors that induced Libya to give up its weapons programs are debatable. Many Bush administration officials have emphasized the U.S.-led 2003 invasion of Iraq, as well as the October 2003 interdiction of a ship containing nuclear-related components destined for Libya, as key factors in Tripoli’s decision. But outside experts argue that years of sanctions and diplomatic efforts were more important.

    Libya erupted into civil war in February 2011, beginning as a clash between peaceful political protestors and the government. The situation degenerated into armed conflict between loyalist Gaddafi forces and rebel militias and culminated with a toppled regime and an elected General National Congress in August 2012. Disarmament efforts were halted in February 2011 due to the conflict but no chemical or biological weapons were used by either side. U.S. intelligence sources said that the stockpiles of these weapons remain secure. Libya today is again on the path to destroying its weapons of mass destruction capabilities and stockpiles.

    The following chronology summarizes key events in the U.S.-Libyan relationship, as well as weapons inspection and dismantlement activities in Libya since its 2003 pledge.


    Skip to: 1970s, 1980, 1981, 1982, 1986, 1988, 1989, 1992, 1993, 1995, 1996, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2016, 2018.



    May 26, 1975: Codifying a commitment to forswear nuclear weapons, Libya ratifies the NPT seven years after it was first signed by the regime of King Idris al-Sanusi.

    December 2, 1979: A mob attacks and sets fire to the U.S. embassy in Tripoli. Embassy officials are subsequently withdrawn and the embassy shut down.

    December 29, 1979: The U.S. government places Libya on a newly created list of state sponsors of terrorism. Countries on the list are subject to a variety of U.S. sanctions.

    1978-1981: Libya purchases more than 2,000 tons of lightly processed uranium from Niger. The Soviet Union completes a 10 megawatt nuclear research reactor at Tajoura.


    July 1980: Libya’s safeguards agreement with the International Atomic Energy Agency (IAEA) enters into force. Such agreements allow the IAEA to inspect certain nuclear-related facilities within a country to verify that the government is not misusing civilian nuclear programs for illicit military purposes.

    Libya subsequently pursues clandestine nuclear activities related to both uranium enrichment and plutonium separation. Both plutonium and highly enriched uranium can be used as fissile material in nuclear weapons.

    May 6, 1981: The United States closes Libya’s embassy in Washington and expels Libyan diplomats.

    August 19, 1981: U.S. aircraft shoot down two Libyan combat jets that fired on them over the Mediterranean Sea.

    January 19, 1982: Libya ratifies the Biological Weapons Convention (BWC). The BWC prohibits states-parties from developing, producing, and stockpiling offensive biological agents.

    January 7, 1986: President Ronald Reagan issues an executive order imposing additional economic sanctions against Libya in response to Tripoli’s continued support for international terrorism, including two December 1985 attacks at airports in Rome and Vienna. The order bans most Libyan imports and all U.S. exports to Libya, as well as commercial contracts and travel to the country. Libyan assets in the United States are also frozen. Reagan authorizes the sanctions under the authority of several U.S. laws, including the International Emergency Economic Powers Act (IEEPA).

    April 15, 1986: U.S. forces launch aerial bombing strikes against Libya in response to Tripoli’s involvement in an April 5 terrorist attack that killed two American servicemen at a Berlin disco.

    December 21, 1988: Pan Am Flight 103 en route from London to New York explodes over Lockerbie, Scotland, killing all 259 people on board and 11 bystanders on the ground. In November 1991, investigators in the United States and United Kingdom name two Libyan officials as prime suspects in the bombing.

    September 19, 1989: The French airliner UTA Flight 772 bound for Paris explodes, killing all 171 people on board. Investigating authorities find evidence of terrorism and indict two Libyan suspects in 1991.


    January 21, 1992: The UN Security Council adopts Resolution 731 demanding that Libya surrender the suspects in the Pam Am bombing, cooperate with the Pan Am and UTA investigations, and pay compensation to the victims’ families.

    March 31, 1992: The Security Council adopts Resolution 748 imposing sanctions on Libya, including an arms embargo and air travel restrictions.


    November 11, 1993: The Security Council adopts Resolution 883 which tightens sanctions on Libya. The resolution includes a limited freeze of Libyan assets as well as a ban on exports of oil equipment to Libya.


    July 1995: According to the IAEA, Libya makes a “strategic decision to reinvigorate its nuclear activities, including gas centrifuge uranium enrichment.”

    Gas centrifuges can enrich uranium for use in nuclear reactors as well as for fissile material in nuclear weapons.


    April 1996: Libya joins the African Nuclear-Weapon-Free Zone by signing the Treaty of Pelindaba. The treaty prohibits member states from developing, acquiring, and possessing nuclear weapons, but has not yet entered into force.

    August 5, 1996: The Iran-Libya Sanctions Act (ILSA) becomes law. The act authorizes the president to impose sanctions against foreign companies that invest more than $40 million a year in Libya’s oil industry.


    April 5, 1999: Libya hands over two suspects--each reportedly linked to Libyan intelligence--to Dutch authorities for trial in the bombing of Pam Am Flight 103.

    Immediately following the handover, as well as France’s acknowledgement that Tripoli had cooperated with French officials investigating the UTA bombing, the Security Council suspends sanctions against Libya originally imposed in 1992.

    May 1999: Libyan officials offer to eliminate their chemical weapons programs during secret talks with the United States, according to Martin Indyk, then assistant secretary of state. In a March 10, 2004 Financial Times article, Indyk reveals that U.S. officials insisted Libya reach a settlement with the Pan Am victims’ families, as well as accept responsibility for the bombing, before Washington negotiate with Libya about its chemical weapons.

    1999-2000: U.S. intelligence agencies begin to obtain new information that Libya is “reinvigorating its nuclear, missile, and biological [weapons] programs,” according to a March 31, 2005 report from the Commission on the Intelligence Capabilities of the United States Regarding Weapons of Mass Destruction. By 2000, “information was uncovered that revealed shipments of centrifuge technology from the [proliferation network run by former Pakistani nuclear scientist Abdul Qadeer Khan] were destined for Libya,” the report says.

    Following the suspension of UN sanctions, Libya also begins increasing its efforts to obtain chemical weapons. According to a 2003 CIA Report, Tripoli reestablishes “contacts with sources of expertise, parts, and precursor chemicals abroad, primarily in Western Europe.”


    January 31, 2001: Three judges hand down verdicts in the Pan Am trial. One man, Abdel Baset Ali Mohmed Al-Megrahi, is found guilty of 270 counts of murder. The other suspect, Lamen Khalifa Fhimah, is acquitted.

    November 19, 2001: Speaking at the BWC Review Conference, Undersecretary of State for Arms Control and International Security John Bolton states that Libya may be violating the treaty by actively seeking to develop or deploy offensive biological weapons. This is the first time the United States has accused noncompliant states by name at a diplomatic conference.


    May 6, 2002: Bolton indicates in a speech to the Heritage Foundation that Libya and Syria received dual-use technology that could be used for producing biological weapons through trade with Cuba. Dual-use goods are items having both civilian and military uses.

    August 3, 2002: President George W. Bush signs the “ILSA Extension Act of 2001” which extends the provisions of the Iran-Libya Sanctions Act for an additional five years and lowers the $40 million investment threshold for the possible imposition of sanctions to $20 million.


    February 12, 2003: CIA Director George Tenet, in written testimony to Congress, notes “Libya clearly intends to re-establish its offensive chemical weapons capability.”

    Early March 2003: Libyan intelligence officials approach British intelligence officials and offer to enter negotiations regarding the elimination of Libya’s WMD programs. The subsequent negotiations, which include U.S. officials, are kept secret.

    Former National Security Council official Flynt Leverett later writes in a January 23, 2004 New York Times article that Washington offers an “explicit quid pro quo” to Tripoli regarding its WMD programs. U.S. officials indicate that the United States will remove its sanctions on Libya if the latter verifiably dismantles these programs, according to Leverett.

    The meeting occurs prior to the U.S.-led invasion of Iraq later that month.

    April 5, 2003: Bolton says in an interview with Radio Sawa that the invasion of Iraq “sends a message” to Libya, as well as Iran and Syria, “that the cost of their pursuit of weapons of mass destruction is potentially quite high.”

    September 12, 2003: In a 13-0 vote, the Security Council formally lifts sanctions imposed on Libya. The United States and France abstain. The Security Council’s action comes in response to Libya’s August 15 agreement to compensate the victims of the Pan Am attack, as well as Tripoli’s formal acceptance of responsibility for that bombing.

    Libya agreed September 11 to offer additional compensation to the families of the 1989 UTA bombing victims. Libya first agreed in 1999 to pay the families, but agreed to increase the amount after the Pan Am victims were promised more. A final agreement is reached in January 2004.

    U.S. Ambassador James B. Cunningham explains that the United States will not lift sanctions because of “serious concerns about other aspects of Libyan behavior,” including Tripoli’s WMD programs. Cunningham states that “Libya’s continued nuclear infrastructure upgrades raise concerns.” He accuses Tripoli of “actively developing biological and chemical weapons.”

    Testifying before the House International Relations Committee four days later, Bolton reiterates his previous threat stating that countries developing WMD “will pay a steep price for their efforts.”

    October 4, 2003: German and Italian authorities interdict a ship en route to Libya containing centrifuge components manufactured in Malaysia. Bush later touts the interdiction as a key intelligence success during a February 11, 2004 speech at the National Defense University. Some U.S. officials subsequently assert that the interdiction played a major role in convincing Libya to come clean on its weapons programs.

    December 19, 2003: Libya’s Foreign Ministry publicly renounces the country’s WMD programs. Tripoli promises to eliminate its chemical and nuclear weapons programs, adhere to its commitments under the NPT and BWC, as well as accede to the Chemical Weapons Convention (CWC). Libya also promises to limit the range and payloads of its missiles to conform to guidelines set by the Missile Technology Control Regime (MTCR). Additionally, Libya agrees to conclude an additional protocol to its IAEA safeguards agreement. The protocol expands the IAEA’s authority to check for clandestine nuclear activities. Libya invites inspectors to verify compliance with the agreements and assist in the dismantling of its weapons programs.

    U.S. and British officials hail the announcement. Bush says that “far better” relations between Washington and Tripoli are possible if the latter fully implements its commitments and “demonstrates its seriousness.” Bush promises U.S. help to “build a more free and prosperous” Libya if the country achieves “internal reform.”

    December 27, 2003: IAEA Director-General Mohamed ElBaradei visits Libya to begin the process of assessing and verifying Libya’s nuclear dismantlement activities.


    January 4, 2004: The London Sunday Times publishes an interview with Gaddafi’s son, who reports that Libya obtained designs for a nuclear weapon from the Khan network.

    January 6, 2004: Libya ratifies the Comprehensive Test Ban Treaty, which prohibits the explosive testing of nuclear weapons. The treaty has not yet entered into force.

    Tripoli also accedes to the CWC. Under the convention, Libya must completely destroy its chemical weapons stockpiles and production capacity by April 29, 2007. Upon joining the CWC, Libya declares the possession of its chemical weapons materials and capabilities as follows: 24.7 metric tonnes (MT) of sulfur mustard; 1,390 MT of precursor chemicals; 3,563 unloaded chemical weapons munitions (aerial bombs); and 3 former chemical weapons production facilities. The OPCW inspections verify these materials and capabilities.

    January 18, 2004: U.S. and British officials arrive in Libya to begin elimination and removal of WMD designs and stockpiles. Assistant Secretary of State for Verification and Compliance Paula DeSutter later tells the Senate Foreign Relations Committee February 26 that the Libyan officials are “forthcoming about the myriad aspects” of Libya’s WMD programs.

    January 24, 2004: Representative Tom Lantos (D-Calif.), the ranking minority member of the House International Relations Committee, becomes the first U.S. lawmaker to visit Libya in decades.

    January 27, 2004: U.S. officials airlift about 55,000 pounds of documents and components from Libya’s nuclear and ballistic missile programs to the United States. The nuclear-related material includes uranium hexafluoride (the feedstock for centrifuges), two complete second-generation centrifuges from Pakistan, and additional centrifuge parts, equipment, and documentation.

    On March 15, Secretary of Energy Spencer Abraham calls the airlift “only the tip of the iceberg,” representing just 5 percent of the total amount of material the United States will eventually recover from Libya.

    February 4, 2004: Khan reveals that, for two decades, he secretly provided North Korea, Libya, and Iran with technical and material assistance for making nuclear weapons.

    February 20, 2004: The IAEA releases a report detailing Libya’s noncompliance with its safeguards agreement and outlining Tripoli’s nascent nuclear program. Specifically, the report describes Libya’s gas centrifuge-based uranium-enrichment program, imports of nuclear material, and designs of facilities for uranium conversion. Libya’s IAEA safeguards agreement required Tripoli to report some of these activities, but the government failed to do so.

    The report says that Libya ordered 10,000 advanced centrifuges and received two of them in 2000. Moreover, the report discloses that Libya secretly separated small amounts of plutonium from the spent fuel of the Tajuora Research Reactor during the 1980s.

    Although the report states that Libya received nuclear weapons design documents from the Khan network, the IAEA cites no evidence that Libya ever undertook steps to build a nuclear weapon.

    February 26, 2004: The United States lifts its Libya travel ban. U.S. citizens are allowed to make travel-related expenditures in Libya, and businesses may enter negotiations to re-acquire pre-sanctions holdings inside Libya. The United States also offers Libya the possibility of opening a diplomatic interests section in Washington.

    DeSutter tells the Senate Foreign Relations Committee the same day that Libya’s decision to abandon its weapons programs should become “a model for other proliferators to mend their ways and help restore themselves to international legitimacy.”

    February 27, 2004: The Organization for the Prohibition of Chemical Weapons (OPCW), the international body charged with verifying CWC compliance, confirms that Libyan officials provided a “partial initial declaration of their chemical weapons stockpiles” and promised a complete declaration to the organization by March 5, 2004.
    The OPCW begins oversight of chemical weapons destruction activities in Libya.

    February 28, 2004: At the end of an African Union summit, Gaddafi calls upon other states to abandon their WMD programs. Nuclear weapons, he says, make states less secure.

    March 4, 2004: The OPCW reports that “[o]ver 3,300 [empty] aerial bombs, specifically designed to disperse chemical warfare agent, have been individually inventoried, then irreversibly destroyed under stringent international verification.”

    March 5, 2004: Libyan officials submit a complete declaration of the state’s chemical weapons stockpile and facilities.

    March 19, 2004: Two OPCW inspection teams completed the initial inspection and verified Libya's January declaration.



    March 8, 2004: The United States, with assistance from British and IAEA officials, arranges for 13 kilograms of highly enriched uranium, a fissile material, to be airlifted from Libya to Russia for disposal.

    March 10, 2004: Libya signs an additional protocol to its IAEA safeguards agreement and reaffirms a December 29 commitment to behave as if the protocol had already entered into force.

    DeSutter tells the House International Relations Committee that the United States has removed five 800 kilometer range Scud-C missiles from Libya, as well as additional missile and centrifuge components.

    The IAEA Board of Governors adopts a resolution declaring that Libya’s past clandestine nuclear activities “constituted noncompliance” with its IAEA safeguards agreement. Nonetheless, the board welcomes the cooperation and openness of Libyan officials since December 2003 and recommends that ElBaradei report Libya’s noncompliance to the Security Council “for information purposes only.” The IAEA is required to report noncompliance with safeguards agreements to the Security Council, which can then take action against the offending state.

    March 23, 2004: Assistant Secretary of State for Near Eastern Affairs William Burns meets with Libyan officials, including Gaddafi, in Tripoli. A State Department spokesperson calls the meetings “constructive” and reflective of the “step-by-step normalization” of relations between Libya and the United States. Burns is the most senior U.S. official to visit Libya since 1969.

    April 22, 2004: In response to the March IAEA resolution, the Security Council issues a president statement “commending” Libya for its cooperation with the agency.

    April 23, 2004: The White House terminates the application of ILSA with respect to Libya. Press Secretary Scott McClellan also announces that the Treasury Department has modified sanctions imposed under the authority of IEEPA. McClellan notes that “the resumption of most commercial activities” between Libya and the United States will now be permitted.

    May 13, 2004: Libya announces it will end military trade with countries it deems “source[s] of concern for the proliferation of weapons of mass destruction.” U.S. officials explain that the Libyan announcement follows a private agreement for Libya to end all its military dealings with Syria, Iran, and North Korea. However, the Libyan foreign ministry later denies that the announcement is aimed at Syria.

    May 26, 2004: Libya submits its initial declarations required by its additional protocol arrangement with the IAEA.

    May 28, 2004: ElBaradei issues a report to the IAEA board detailing the agency’s progress in verifying Libya’s declarations regarding its nuclear program. According to the report, “Libyan authorities have provided prompt, unhindered access to all locations requested by the [a]gency and to all relevant equipment and material declared to be in Libya.”

    Speaking June 14 to the board, ElBaradei says questions remain regarding the origin of nuclear material Libya imported during 2000 and 2001, as well as the source of enriched uranium particles found on Libya’s centrifuge equipment. The agency has contacted other governments to investigate entities involved in providing nuclear technology to Libya.

    June 28, 2004: Announcing that Washington and Tripoli will resume direct diplomatic ties, Burns inaugurates a new U.S. Liaison Office in Libya.

    September 20, 2004: The United States lifts most of its remaining sanctions on Libya. Bush terminates the national emergency declared in 1986 under IEEPA, as well as revokes related executive orders. This action ends the remaining sanctions under IEEPA and ends the need for Treasury Department licenses for trade with Libya.

    The United States also permits direct air flights between the two countries, as well as unfreezes Libyan assets in the United States. Additionally, Bush waives prohibitions on extending certain U.S. export assistance programs to Libya and on the ability of U.S. taxpayers to claim credits for taxes paid to Libya.

    Libya is still subject to some sanctions as it remains on the U.S. list of state sponsors of terrorism. These sanctions include prohibitions on arms exports and Department of Defense contracts. The United States also is required to oppose loans from international financial institutions to such countries and impose export controls on dual-use items.

    Two days later, DeSutter tells the House International Relations Committee that verification of Libya’s disarmament tasks is “essentially complete,” adding that the United States, working with the United Kingdom, has completed verifying “with reasonable certainty that Libya has eliminated, or has set in place the elimination of” its weapons programs.

    August 30, 2004: ElBaradei issues another report to the IAEA board stating that information Tripoli has given to the agency about its past nuclear activities “appear[s] to be consistent with the information available to and verified by” the IAEA.

    According to the report, the IAEA continues to investigate several outstanding issues regarding Libya’s nuclear weapons program, particularly assistance Tripoli received from the Khan network. Cooperation from other countries is “essential” for determining the role of the network in supplying Libya, the report adds.

    October 11, 2004: European Union foreign ministers lift a 20 year-old arms embargo on Libya, allowing EU countries to export arms and other military equipment to that country. Part of the EU rationale for lifting the embargo is to improve Libya’s capacity to patrol its maritime borders and prevent illegal immigration to the EU from North Africa, a particular concern of southern European states such as Italy.

    European arms transfers are still governed by the EU’s Code of Conduct on Arms Exports and national export control laws.


    March 25, 2005: In a letter to The Washington Post, White House Press Secretary Scott McClellan declares for the first time publicly the U.S. assessment that the uranium hexafluoride found in Libya originated in North Korea. According to McClellan, this material was transferred to Libya via the A.Q. Khan illicit trafficking network.

    October 20, 2005: Libya signs an agreement with Russian nuclear fuel manufacturer TVEL to provide its Tajoura research reactor with low-enriched uranium (LEU) as part of an effort to convert the reactor from using HEU to LEU.


    May 15, 2006: Secretary of State Condoleezza Rice announces the U.S. establishment of full diplomatic relations with Libya. As part of that move, President George W. Bush submits a report to Congress certifying that Tripoli had not engaged in acts of terrorism in the previous six months and had provided assurances that it would not support terrorism, thereby allowing Libya to be removed from the list of state sponsors of terrorism.

    June 26, 2006: The United Kingdom and Libya sign a “Joint Letter of Peace and Security,” in which London pledges to seek UN Security Council action if another state attacks Libya with chemical or biological weapons and pledges to aid Libya in strengthening its defense capabilities.  Both states also announce that they will work jointly to combat the proliferation of weapons of mass destruction.

    July 27, 2006: IAEA and U.S. National Nuclear Security Administration officials help remove the last remaining quantity of fresh HEU from Libya.  Three kilograms of Russian-origin HEU from the Tajoura research reactor in Libya are returned to Russia for disposal.

    December 2006: The OPCW establishes Dec. 31, 2010 as the deadline for Libya to destroy its mustard gas stockpiles and Dec. 31, 2011 as the deadline to destroy its remaining chemical weapon precursors.


    June 14, 2007: Libya annuls its contract on chemical weapons destruction with the United States due to dissatisfaction with its provisions on liability, financing, and facility ownership. Under its agreement with the Organization for the Prohibition of Chemical Weapons, these chemicals must be eliminated by the end of 2010. Libya did not indicate how it intended to meet this commitment.

    July 25, 2007: France and Libya sign a memorandum of understanding on nuclear energy cooperation.  The agreement outlines a plan for the eventual construction of a nuclear desalination plant.


    January 3, 2008: Libyan Foreign Minister Abdel Rahman Shalgam pays an official visit to the United States and signs a Science and Technology Cooperation Agreement. This is the first official visit by a Libyan Foreign Minister to the United States since 1972.

    August 14, 2008: The United States and Libya sign the U.S -Libya Claims Settlement Agreement, providing full compensation for victims of the 1988 Lockerbie bombing and the bombing of the Berlin disco. Under the terms of the agreement, Secretary of State Condoleezza Rice certified to Congress that Libya paid $1.5 billion to cover terrorism related claims against Tripoli. The agreement also addressed Libyan claims arising from U.S. military actions in Tripoli and Benghazi in 1986 to the amount of $300 million.

    September 12, 2008: An IAEA Board report says that the agency has completed its investigation of Libya’s past nuclear activities and found that Tripoli had addressed all of the outstanding issues related to its past nuclear activity.


    November 20, 2009: Libya unexpectedly halts the shipment of the remaining 5.2 kilograms of HEU in spent fuel from its Tajoura research reactor. The material was scheduled to be flown to Russia for disposal that same month as part of an agreement between the Libya, Russia, and the United States. According to State Department cables obtained by the Guardian in 2010, U.S. Energy Department experts said that concerns about the safety and security of the material presented a high level of urgency, and the HEU needed to be removed within one month.

    December 21, 2009: Libya allows a Russian-chartered plane to leave the country carrying the last of its HEU spent fuel stocks for disposal in Russia after a month-long delay.

    December 2009: The OPCW approves Libya’s request to extend the deadline for the destruction of its mustard gas stockpiles from December 2010 to May 2011. According to the OPCW report for 2009, Libya destroyed 39% of its chemical weapons precursors by the end of the year but destruction of its mustard gas had not yet begun.


    July 2010: The State Department’s arms control Compliance Report says that Libya is complying with its Biological Weapons Convention and  nuclear nonproliferation obligations. It also says that Libya has made progress destroying its chemical weapons stockpile but has not yet met its obligations to adopt legislation to implement the Chemical Weapons Convention.

    October 2010: The destruction of one of Libya's chemical agents, sulfur mustard, is initiated.



    February 23, 2011: OPCW spokesperson Michael Luhan tells the Associated Press that Libya destroyed “nearly 13.5 metric tons” of its mustard gas in 2010, accounting for “about 54 percent of its stockpile.”

    February 25, 2011: Citing security concerns due to ongoing political unrest, U.S. officials announce the suspension of U.S. embassy operations in Libya.

    February 26, 2011: United Nations Security Council unanimously adopts Resolution 1970 condemning the lethal actions taken by Gaddafi forces against civilian political protestors.  The resolution also places financial and travel restrictions on regime officials.  The OPCW announced that machinery breakdowns brought to a halt ongoing destruction of sulfur mustard amid rising tensions.

    March 17, 2011: The United Nations Security Council adopts Resolution 1973 authorizing an international response to the Libyan civil war.  The resolution creates a no-fly zone over Libya, strengthens an arms embargo and allows forcible inspection of suspected weapons trafficking ships and planes traveling to the country.

    March – October 2011: NATO enforces the no-fly zone established by Resolution 1973.  Fighting continues between loyalist Gaddafi forces and the rebel militia.  The National Transition Council (NTC) is generally internationally recognized as the legitimate government of Libya.  U.S. officials publicly assure that remaining sulfur mustard agent and existing weapons stockpiles are secure during the ongoing conflict.

    September 23, 2011: The IAEA confirms a cache of yellowcake uranium was discovered in an abandoned nuclear materials warehouse belonging to the Gaddafi regime.  The material is not deemed a high-level security risk because it is not suitable for use in a weapon.

    October 20, 2011: Gaddafi is found and killed by rebel forces in the town of Sirte in western Libya.  NATO military operations end and the NTC forms an interim government and schedules elections.

    November 1, 2011: The NTC officially notifies the OPCW of what was determined to be two undeclared chemical weapons stockpiles from the previous regime.  The NTC cooperates with OPCW plans to resume destruction of weapons material.

    November 28, 2011: The new government in Tripoli submitted an official declaration of the weapons to the OPCW.

    December 2011: The IAEA visits the Tajoura Nuclear Facility in Tripoli and a uranium concentrate storage facility in Sabha.  The nuclear watchdog organization informs the UN Security Council that no previously declared stockpiles had been disturbed or reported missing as a result of the conflict.



    January 17-19, 2012: OPCW inspectors visited Libya to verify the previously undisclosed chemical weapons. The inspection’s purpose is two-fold, for verifying the new declaration with regard to types and quantities of chemical weapons, and for helping the Libyan government in determining whether another set of discovered materials could be declared under the provisions of the CWC.

    April 2012: Libya fails to meet the international April 29, 2012 deadline for destruction of remaining chemical weapons.  Libya submits a working paper to the Preparatory Committee for the 2015 Review Conference of the Parties to the Treaty on the Non-Proliferation of Nuclear Weapons affirming the country’s commitment to nuclear disarmament and compliance with IAEA authorities and regulations.

    April 25, 2012: OPCW announced it would start the destruction of the mustard gas stockpile. Canada aids in the funding of the destruction.

    May 2012: The government submits a revised plan to the OPCW to complete destruction activities by December 2016 with destruction operations to resume in March 2013.  Current Libyan behavior is indicative of a cooperative relationship with international nonproliferation standards.

    May 27 – 28, 2012: The Director-General, Ambassador Ahmet Üzümcü, visited Tripoli and met the Libyan Foreign Minister, H.E. Ashour Saad Ben Khaial, and the Under Secretary of the Ministry of Foreign Affairs, Dr. Muhammad Abdul Aziz. The Libyan authorities have reaffirmed their destruction of remaining chemical weapons as soon as possible.

    August 2012: The NTC transfers power to the elected General National Congress.  Mohammed Magarief is elected by the body as interim head of state.

    September 20, 2012: The IAEA approves and signs Libya’s Country Programme Framework (CPF) for the period of 2012 to 2017.  The medium-term planning agreement identifies how nuclear technology and resources will be used for economic development in the country.  The IAEA also conducted two missions to Libya in 2012 to review and support nuclear security and infrastructure.


    April 20, 2013: Destruction of the remaining 8.82 metric tons of sulfur mustard stored at Ruwagha begins.

    May 4, 2013: Libya completes the destruction of 22.3 metric tons of Category 1 chemical weapons, or nearly 85% of the total declared stocks under OPCW verification.

    The remaining chemical weapon stockpile is comprised of about 2.45 metric tons of polymerised sulphur mustard and 1.6 metric tons of sulphur mustard loaded in projectiles, bombs and bomb cartridges, as well as 846 metric tons of precursor chemicals.


    January 26, 2014: Libya completes the destruction of its category 1 chemical weapons. The OPCW verifies that the destruction is completed. The remaining category 2 materials are scheduled to be destroyed by the end of 2016. 


    February 3, 2016: Libya requests assistance from the OPCW in destroying its remaining category 2 chemical weapons. 

    July 16, 2016: The Libyan government requests assistance in removing chemical weapons precursors from the country and eliminating them out of the country. 

    July 20, 2016: The OPCW approves Libya's request for assistance. 

    July 22, 2016: The UN Security Council endorses the OPCW's decision to assist in transporting the precursors out of the country in Resolution 2298. A number of countries, including Canada, Denmark, Finland, France, Germany, Italy, Malta, Spain, the United Kingdom, and the United States, offer technical and financial assistance for the removal and destruction. 

    August 27, 2016: The OPCW confirms that the precursor chemicals were removed from Libya on Danish ships and brought to Germany for destruction. 


    January 11, 2018: The OPCW confirms that the Category 2 chemical materials removed from Libya and transported to Germany had been destroyed, marking the complete destruction of Libya's chemical weapons arsenal.

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