Advancing the CTBT and Reinforcing the Global Norm Against Nuclear Testing

Sept. 26, 2025

Civil Society Statement to the 14th Article XIV Conference on Facilitating Entry into Force of the CTBT

Since the conclusion of negotiations that led to the 1996 Comprehensive Nuclear-Test-Ban Treaty (CTBT), nuclear explosive testing has become taboo.

Though it has not yet formally entered into force, the CTBT is one of the most successful and valuable agreements in the long history of nuclear nonproliferation, arms control, and disarmament. Without the option to conduct nuclear explosive tests, it is more difficult, although not impossible, to develop, prove, and field new warhead designs.

With signatures by 187 states, all CTBT states-parties agreed to create a treaty that prohibits “any nuclear weapons test explosion, or any other nuclear explosion,” no matter what the yield or where it is conducted. The CTBT Organization operates a fully functional International Monitoring System (IMS) to detect and deter violations of the CTBT.

Unfortunately, the door to the renewal of nuclear testing remains open. Responsible states and civil society leaders must remain vigilant and take meaningful steps to reinforce the non-testing norm, maintain financial and technical support for the Comprehensive Test Ban Treaty Organization (CTBTO), and the IMS, and to step up diplomatic and political engagement to encourage the remaining Annex 2 states to finally initiate action to sign and ratify the Treaty so they can join the nonproliferation mainstream.

Civil society greatly appreciates the support of the states gathered at this 14th Article XIV Conference on Facilitating Entry Into Force and the special efforts of the co-chairs from Panama and Norway. We note with appreciation the efforts of dozens of states described in the report on “Activities Undertaken by Signatory and Ratifying States.”

But we all must recognize that progress, and the preservation of the taboo against nuclear explosive testing, will require a much more robust and sustained effort on the part of all of the friends of the CTBT.

Why? Since 2023, the prospects for signature and ratification have deteriorated and there are dangerous signs that one or more of the nuclear-armed states may resume nuclear testing in the near future. This would likely set off a chain-reaction of nuclear testing, the likes of which we have not seen in decades.

Among the nine, Annex 2 CTBT “hold-out” states are several nuclear-armed states that have not signed or ratified the treaty. This list includes:

• China
• the Democratic People’s Republic of Korea (DPRK)
• India
• Israel
• Pakistan
• the United States, and
• the Russian Federation, which unhelpfully withdrew its ratification of the treaty.

In January 2020, the (DPRK) announced it "will no longer observe its self-imposed moratorium on nuclear testing." To date, it has not yet resumed nuclear testing but has vowed to increase the size and diversity of its nuclear arsenal. The DPRK has refused to engage in talks about measures to limit or reduce its nuclear activities and its nuclear arsenal. Chinese and Russian officials do not appear to have encouraged the DPRK to join the CTBT.

In 2024, President Donald Trump’s former national security advisor called for a resumption of U.S. nuclear testing. Since Trump’s second inauguration, however, there appear to be no tangible signs that the United States is preparing to resume nuclear testing. In April, the administrator for the National Nuclear Security Administration, Brandon Williams, testified before Congress that he “would not advise testing” nuclear weapons above the criticality threshold. Such statements are welcome but not sufficient.

U.S. ratification of the treaty is manifestly in the interest of U.S. and global security. The United States has not conducted a nuclear test explosion in 33 years and has no technical, military, or political reason to resume testing. The case for ratification and strengthening the barriers against testing by others is even stronger than when it was last considered by the Senate in 1999. We call on the current U.S. government to help reinforce the global non-testing norm, refrain from measures that are contrary to the object and purpose of the treaty, and reconsider ratification of the CTBT.

For its part, China continues to express rhetorical support for the CTBT, but there has been no serious consideration of ratification of the CTBT by leaders in Beijing, Chinese has also not provided any credible explanation for its years of delay in moving forward with consideration of CTBT ratification.

China, which says it has no intention to resume nuclear testing, could provide much needed global leadership and help reinforce the non-testing norm, and put pressure on other CTBT hold-out states by moving forward with its ratification process.

Prompted by courageous citizen activists and independence leaders in Kazakhstan, the Russian leadership halted nuclear testing in 1990. In the years that followed, Russia actively supported the negotiation of the CTBT and ratified the treaty in the year 2000.

Unfortunately, in the name of achieving “symmetry” with the United States in all areas of nuclear policy, Russia de-ratified the treaty in 2023. This is a backward step that undermines the broader nuclear nonproliferation regime.

Meanwhile, the United States, China, and Russia all continue to engage in weapons-related activities at their former nuclear testing sites. Although the IMS is operational and far more effective than originally envisioned, very low-yield nuclear test explosions can still be difficult to detect without on-site monitoring equipment or inspections, which will not be in place until after entry into force.

In the absence of new voluntary confidence-building measures, there remains a risk that activities at these former nuclear testing sites might be misconstrued as nuclear weapon test explosions or might be cited as a cynical excuse for another state to openly resume nuclear testing.

To address concerns about clandestine activities at former test sites, states at this conference should collectively and individually call upon CTBT signatory states to develop technical methods that would support voluntary confidence-building measures – to be implemented with support from independent scientific experts and/or the CTBT – that are designed to detect and deter possible low-level, clandestine nuclear testing.

We urge all CTBT states-parties, especially those with active nuclear test sites, to engage in this important technical dialogue to improve capabilities to ensure compliance before and after the treaty's entry into force.

With these challenges in mind, CTBT states parties cannot afford to simply express rhetorical support in the months and years ahead.

As we approach the 30th anniversary of the conclusion of negotiations that produced the CTBT, we must go beyond business as usual.

Going forward, we urge the next Article XIV co-chairs, Sweden and the Philippines, along with other friends of the CTBT states, to pursue even more energetic, higher-level bilateral and multilateral diplomacy. We must seek to build support for the CTBT at the UN General Assembly, the Security Council, the 2026 NPT Review Conference, the CTBTO in Vienna, and beyond.

As representatives of civil society, we offer the following observations and recommendations for all states-parties to consider and pursue.

1. Seek a joint statement reaffirming support for the CTBT from the five nuclear-armed states-parties to the NPT. Such a statement should reaffirm their support for the CTBT, its prompt entry into force, and pledge that they will not take any action that would “defeat the object or purpose of the treaty" pending its entry into force. Such a statement might reaffirm the elements contained in UN Security Council Resolution 2310, which was approved by China, Russia, the United States, and other members of the UN Security Council in 2016. Alternatively, the five states could also issue a joint statement reaffirming their support, as CTBT signatories, for entry into force, the global nuclear test moratorium, and the full and effective operation of the CTBTO, in the context of their P5 Process discussions.
2. Pursue Energetic Diplomacy Focused on the Nine Hold-Out States. We welcome recent efforts to secure ratifications from several additional states. But it is now time for this conference and each CTBT state-party to focus on new and creative approaches to overcome the stubborn intransigence of the nine remaining Annex 2 “hold-out” states, which have deprived the international community, and themselves, of the full security benefits of the treaty and its extensive verification system. This will require that heads of state and foreign ministers from friends of the CTBT states engage their counterparts in the hold-out states directly.

This outreach should also extend beyond the five NPT nuclear-armed states.

Since their nuclear detonations in 1998, India nor Pakistan have refused to reconsider the CTBT even though neither country has expressed an interest in, nor technical justification for, renewing nuclear testing. UN Security Council Resolution 1172 paragraph 13 “urges India and Pakistan ... to become Parties to the ... Comprehensive Nuclear Test Ban Treaty without delay and without conditions.” India and/or Pakistan could advance the cause of nuclear disarmament, enhance their national security and nonproliferation reputations, and ease concerns about a resumption of nuclear testing, by converting their unilateral test moratoria into legally binding commitments through the CTBT.

Ratification of the CTBT by Egypt, Iran, and nuclear-armed Israel—all of which must ratify to trigger CTBT entry into force—and Saudi Arabia would reduce nuclear weapons-related security concerns in the region. It would also help create the conditions necessary to achieve their common, stated goal of a Middle East Zone Free of Nuclear Weapons and Other Weapons of Mass Destruction.

A goal of the co-chairs of the Article XIV process, as well as other friends of the CTBT states, should be to approach each of these governments to gain a clearer understanding regarding the circumstances that would allow each to join the CTBT, and to explain what the benefits of joining the CTBT mainstream would be.

North Korea’s push to build up its nuclear weapons capabilities represents another threat to the norm against nuclear testing. All CTBT signatory states should underscore, in multilateral and bilateral fora and in meetings with the government in Pyongyang, that signature and ratification of the treaty would represent a significant step toward denuclearization and help create the conditions for peace and normalization of relations.

In particular, we call upon the leadership of China and Russia, which maintain ties to the DPRK, to press Chairman Kim to reaffirm the DPRK's nuclear test moratorium and, as former CTBTO Executive Secretary Lassina Zerbo proposed in 2018, urge him to sign the CTBT like all the other major nuclear powers have done, and close the Punggye-ri Nuclear Test Site under international supervision.

3. Fully Support the CTBTO. As some states reduce their contributions and technical support for international organizations and institutions, the infrastructure for global peace and security has come under greater and greater stress.

We urge all CTBT states-parties to ensure that the CTBTO has the necessary resources to continue to operate and maintain the IMS, the in-kind technical support to ensure it can modernize and improve its capabilities, and the political, technical, and financial support necessary to fully develop the on-site inspection capabilities called for under the Treaty.

4. Address the Human Cost of Nuclear Testing. Since 1945, there have been 2,056 nuclear-weapons test explosions, not including the devastating U.S. atomic bombings of the cities of Hiroshima and Nagasaki. Of that total, the United States detonated some 1,030 test explosions and the Russian Federation detonated 715.

The CTBT and the de facto global nuclear testing moratoria have helped to reduce health and environmental injury from further nuclear-weapons testing.

However, hundreds of thousands of people have died and millions more have suffered—and continue to suffer—from illnesses directly related to the radioactive fallout from past nuclear test detonations in the southwestern and western United States, islands in the Pacific, in Australia, western China, Algeria, across Russia, in eastern Kazakhstan, India, Pakistan, the DPRK, and elsewhere.

To address the ongoing, adverse health, social, environmental, and enduring consequences of these detonations we need more research, more resources, and more support for nuclear testing victims and we need acknowledgement and apologies for the wrongs committed in the past.

We call on all governments, particularly those responsible for conducting nuclear explosions in the past, to provide the necessary financial and technical support for long term environmental remediation programs, to expand access to health care especially as it relates to treatment of illnesses associated with radiation exposure, and to build independent capacity to monitor, assess, and address the environmental and health needs of the affected communities in the years to come.

Bottom Line

The CTBT and the CTBTO have been vital to global security for more than a quarter century. But norms, like treaties, are only as strong as the commitment behind them.

As we approach the 30th anniversary of the CTBT, governments must do more than issue rhetorical support. We cannot take the treaty, the IMS, or the de facto global nuclear test moratorium for granted.  The CTBT remains within reach. What is needed is political will and courage, and civil society stands ready to support and amplify these efforts.

Endorsed by:

Dr Rebecca Eleanor Johnson, Executive Director, Acronym Institute for Disarmament Diplomacy (AIDD)

Hubert K. Foy, Director & Senior Research Scientist, African Center for Science and International Security (AFRICSIS)*

Daryl G. Kimball, Executive Director, Arms Control Association

Joel Petersson Ivre, Senior Policy Fellow, Asia-Pacific Leadership Network*

Tanya Ogilvie-White, Senior research advisor, Asia-Pacific Leadership Network*

Peter Wilk, Administrative Chair, Back from the Brink Coalition

Dr. Togzhan Kassenova, Senior Fellow, Center for Policy Research, University at Albany*

Jan Kavan, Foreign Policy Advisor, Council of UNGA Presidents*

Oliver Meier, Policy and Research Director, European Leadership Network*

Nikita Gryazin , Policy Fellow, European Leadership Network*

Edan Jules Simpson, Project and Communication Coordinator, European Leadership Network*

Ambassador Thomas Greminger, Executive Director, Geneva Centre for Security Policy (GCSP)*

David A. Koplow, Professor of Law, Georgetown University*

Tariq Rauf, former Head of Verification and Security Policy, IAEA*

Marc Finaud, Vice president, Initiatives pour le désarmement nucléaire (IDN)

Dr. Ulrich Kühn, Head of the Arms Control and Emerging Technologies, Institute for Peace Research and Security Policy at the University of Hamburg (IFSH)

Dr. Tobias Fella, Senior Researcher, Institute for Peace Research and Security Policy at the University of Hamburg (IFSH)

Michael Christ, Executive Director, International Physicians for the Prevention of Nuclear War (IPPNW)

Hideo Asano, Coordinator, Japan Campaign to Abolish Nuclear Weapons*

Dr. Deepshikha Kumari Vijh, Executive Director, Lawyers Committee on Nuclear Policy

Elizabeth Shafer, Board Member, The Lawyers’ Committee on Nuclear Policy*

Benetick Kabua Maddison, Executive Director, Marshallese Educational Initiative

MATSUI Kazumi, President, Mayors for Peace*

Bruce Fred Knotts, President/CEO, NGO Committee on Disarmament, Peace, and Security*

Aaron Tovish, Senior Advisor, NoFirstUse Global*

Ivana Nikolić Hughes, President, Nuclear Age Peace Foundation

Bill Kidd MSP, Co-President, Parliamentarians for Nuclear Non-Proliferation and Disarmament*

Akira Kawasaki, Executive Committee Member, Peace Boat

Tatsujiro Suzuki, President, Peace Depot*

Denise Duffield, Associate Director, Physicians for Social Responsibility-Los Angeles

Robert Goldston, Professor, Princeton University*

Frank Niels von Hippel, Senior Research Physicist and Professor of Public and International Affairs emeritus, Princeton University*

Jennifer Allen Simons, Founder and President, The Simons Foundation Canada*

Tomohiko Aishima, Executive Director for Peace and Global Issues, Soka Gakkai International*

Scott Yundt, Executive Director, Tri-Valley Communities Against a Radioactive Environment

Jane Kinninmont, Chief Executive. United Nations Association - UK

Matthias Grosse Perdekamp, Professor of Physics, University of Illinois, Urbana Champaign*

Rebecca Davis Gibbons, Associate Professor, University of Southern Maine*

Sean Arent, Nuclear Weapons Abolition Program Manager, Washington Physicians for Social Responsibility

Jacqueline Cabasso, Western States Legal Foundation*

Women's International League for Peace and Freedom (WILPF)

Cherrill Spencer, Co-Chair DISARM/End Wars Committee, Women's International League for Peace and Freedom US

Garry Jacobs, President, World Academy of Art and Science

Magritte Gordaneer, Program Manager, Physicians for Social Responsibility

Susan F. Burk, Former Special Representative of the President for Nuclear Nonproliferation

*affiliation listed for identification purposes only

[This statement was co-organized by the Arms Control Association (ACA) and the Lawyers Committee on Nuclear Policy (LCNP) and delivered by Shizuka Kuramitsu with ACA.]

For Immediate Release: September 22, 2025

Media Contact: Daryl Kimball, ACA Executive Director, (202) 462-8270 ext. 107

(Washington, D.C.)—Earlier today, Russian President Vladimir Putin said that “Russia is ready to continue to adhere to the central quantitative restrictions under the [New] START Treaty for one year after February 5, 2026.”

In response, ACA Executive Director Daryl Kimball said “President Putin’s proposal is a positive and welcome move, and one that many of us have been advocating. More nuclear weapons will not make the U.S., Russia, or the world safer.”

“If Putin and Trump agree to maintain current strategic nuclear limits after the New Strategic Arms Reduction Treaty (New START) expires and launch talks on more ambitious nuclear disarmament measures, they can help reduce the most immediate existential security threat facing the world,” he said.

“An agreement not to exceed the current strategic nuclear limits would reduce tensions, forestall a costly arms race that no one can win, create diplomatic leverage to curb the buildup of China’s arsenal, and buy time for talks on a broader, more durable, treaty,” Kimball said

“We strongly encourage President Trump to reciprocate Putin’s proposal to maintain existing limits on their long-range nuclear weapons, and we urge the Kremlin and the White House to immediately direct their teams to begin negotiations on a new more comprehensive agreement or agreements that address difficult issues with which the two sides have long struggled.”

For more than a decade, Russia and the United States have failed to engage in meaningful talks designed to verifiably reduce their strategic nuclear arsenals; maintain restrictions on intermediate-range forces and account for and limit sub-strategic nuclear weapons; and establish common-sense limits on strategic missile defense, space-based weapons, and long-range conventional strike weapons.”

“To broaden the disarmament effort, Putin and Trump could also call on China, France, and the UK to report on their total nuclear weapons holdings and freeze their nuclear stockpiles, provided Russia and the United States pursue deeper verifiable reductions in their far larger arsenals,” Kimball suggested.

“A Trump-Putin pledge to maintain mutual restraints on their already massive strategic nuclear arsenals, combined with the resumption of formal U.S.-Russian talks on further nuclear arms reductions, would be a positive and essential step for U.S. and world security,” said Thomas Countryman, Chair of the Board of Directors of the Arms Control Association, and former U.S. Assistant Secretary of State for International Security and Nonproliferation.

The 2010 New START agreement—the last remaining bilateral nuclear arms reduction agreement between the United States and Russia—will expire in 136 days. The agreement limits each side to no more than 1,550 deployed warheads on no more than 700 deployed land-based intercontinental ballistic missiles (ICBMs), submarine-launched ballistic missiles (SLBMs), and strategic bombers.

When previously asked about the expiration of the treaty, Trump said on July 25: “That is a big problem for the world, when you take off nuclear restrictions that’s a big problem.”

Additional Resources:

“U.S.-Russian Nuclear Arms Control Agreements at a Glance“ an ACA Fact Sheet

“After the New START Treaty,” Deep Cuts Commission Fact Sheet, Sept. 15, 2025

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The Arms Control Association is an independent, membership-based organization dedicated to providing authoritative information and practical policy solutions to address the threats posed by the world’s most dangerous weapons. ACA is one of many organizations that has recently issued a “New Call to Halt and Reverse the Nuclear Arms Race.”

Statement from Kelsey Davenport, Director for Nonproliferation Policy, 

Sept. 19, 2025

Today’s UN Security Council vote to restore international sanctions on Iran over its nuclear program does not close the door on diplomacy, but if the United States and Iran do not move swiftly to restart negotiations on a pragmatic, effective nuclear agreement, there is an increased risk that Iran will resume sensitive nuclear activities and a new military crisis between Washington and Tehran could erupt.

The UN measures, which were lifted under Resolution 2231’s endorsement of the 2015 nuclear deal, will reimpose international sanctions on Iran, restrict the country’s nuclear activities, including a prohibition on enrichment, and ban ballistic missile development. Iran has threatened to suspend recently renewed cooperation with the International Atomic Energy Agency (IAEA) in response.

With bold, decisive leadership, Washington and Tehran could still avert snapback and reduce the risk of an escalatory spiral that puts the two countries back on a path to conflict.

Next week, as heads of state gather at the UN General Assembly, there will be an opportunity for U.S. President Donald Trump to extend to Iran a serious diplomatic offer to avert a new nuclear proliferation crisis. Iran’s own proposal to extend snapback, which reportedly does not provide specific timelines on restoring safeguards, is insufficient. Nonetheless, it is another signal that Tehran is interested in diplomatically extending snapback and the Trump administration should test that willingness. 

The United States, with the support of the E3 (France, Germany, and the United Kingdom), should respond by proposing an agreement that would:

• extend the option to snapback UN sanctions for 12 months beyond the October expiration,
• encourage the resumption of direct negotiations between the United States and Iran on a new framework for addressing concerns about Iran’s nuclear activities,
• recognize Iran’s rights to a peaceful, safeguarded nuclear program under Article IV the nuclear Nonproliferation Treaty (NPT),
• call upon Iran to immediately resume full implementation of its legally binding safeguards agreement with the IAEA,
• put in place a voluntary 12-month enrichment moratorium, and
• strengthen the ceasefire Trump announced in June, including with a commitment from both sides to refrain from strikes or support for strikes, while negotiations are underway.

Such an agreement could be endorsed by the UN Security Council, superseding the Sept. 19 resolution that restored UN sanctions on Iran.

A Security Council resolution along these lines will advance international peace and security, without jeopardizing U.S. nonproliferation interests. The resumption of IAEA monitoring and the temporary enrichment moratorium would provide ample early warning if Iran were to resume proliferation-sensitive activities in violation of the Security Council-endorsed arrangements.

The window for reaching such an agreement to avert escalating tensions over snapback is very short. But the door to diplomacy remains open even if the United States and Iran cannot agree on any interim measures before Sept. 28.

If UN sanctions are snapped back, it will be critical for Washington and Tehran to exercise restraint in the coming weeks and focus on resuming negotiations. If both the United States and Iran seek to build pressure and leverage, there is a greater risk that a military conflict will re-erupt.

Iran should refrain from actions that will complicate future diplomatic efforts and drive speculation about its nuclear intentions, such as ending all cooperation with the IAEA, threatening NPT withdrawal, resuming uranium enrichment, or moving enriched uranium. Such actions would raise doubts about Iran's claim that its program is entirely peaceful, may be used a pretext for further military strikes, and will only create new challenges in negotiating a comprehensive nuclear accord.

The United States must recognize that there is no military solution to the Iranian nuclear crisis.  Further strikes at this time risk driving Iran closer to nuclear weapons and following through on its threat to withdraw from the NPT. Furthermore, the Trump administration should make clear to Israel that it will oppose further strikes on Iran’s nuclear program and the targeting of Iran’s nuclear scientists. The Trump administration should also recognize that demanding Iran agree to zero enrichment before negotiations resume is unnecessary and a nonstarter.

Snapback of Security Council resolutions will formally put an end to the 2015 nuclear deal, or Joint Comprehensive Plan of Action (JCPOA). Although restoration of the JCPOA was not a viable technical or political option for the past several years, it continued to serve as a framework for negotiations. The end of the JCPOA era, however, is an opportunity for both sides to pursue creative, pragmatic options for a long-term agreement that recognizes Iran’s peaceful nuclear ambitions, while ensuring it is not used to build nuclear weapons. 

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The Arms Control Association is an independent, nongovernmental, nonpartisan membership organization dedicated to the providing authoritative information and practical solutions to eliminate the threats posed by the world's most dangerous weapons.

Kelsey Davenport is the Director for Nonproliferation Policy, and is a leading expert on nuclear and missile programs in Iran and North Korea and on international efforts to prevent proliferation and nuclear terrorism.

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Media inquiries and interview requests should be directed to [email protected]