Press Contacts: Kelsey Davenport, Nonproliferation Analyst, (202) 463-8270 x102 and Daryl G. Kimball, Executive Director, (202) 463-8270 x107.
Updated: May 2015
A nuclear-weapon-free zone (NWFZ) is a specified region in which countries commit themselves not to manufacture, acquire, test, or possess nuclear weapons. Five such zones exist today, with four of them spanning the entire Southern Hemisphere. The regions currently covered under NWFZ agreements include: Latin America (the 1967 Treaty of Tlatelolco), the South Pacific (the 1985 Treaty of Rarotonga), Southeast Asia (the 1995 Treaty of Bangkok) Africa (the 1996 Treaty of Pelindaba) and Central Asia (the 2006 Treaty of Semipalatinsk).
Article VII of the nuclear Nonproliferation Treaty (NPT), which entered into force in 1970, affirms the right of countries to establish specified zones free of nuclear weapons. The UN General Assembly reaffirmed that right in 1975 and outlined the criteria for such zones. Within these nuclear-weapon-free zones, countries may use nuclear energy for peaceful purposes.
Each treaty establishing a nuclear-weapon-free zone includes a protocol for the five nuclear-weapon states recognized under the NPT-China, France, Russia, the United Kingdom, and the United States-to sign and ratify. These protocols, which are legally binding, call upon the nuclear-weapon states to respect the status of the zones and not to use or threaten to use nuclear weapons against treaty states-parties. Such declarations of non-use of nuclear weapons are referred to as negative security assurances. However, the five nuclear-armed countries have at times signed and ratified a NWFZ protocol and declared conditions reserving the right to use nuclear weapons in certain scenarios against parties to a nuclear-weapon-free zone. For instance, the United States signed the protocol for the African nuclear-weapon-free zone in April 1996 with a declaration that it would reserve the right to respond with all options, implying possible use of nuclear weapons, to a chemical or biological weapons attack by a member of the zone. None of the nuclear-weapon states have signed the relevant protocol for the treaty creating a zone in Southeast Asia because of concerns that it conflicts with the right of their ships and aircraft to have freedom of movement in international waters and airspace. The other three zones do not explicitly rule out the transit of nuclear weapons by nuclear-weapon states through the zones, and the general practice of nuclear-weapon states is not to declare whether nuclear weapons are aboard their vessels.
In addition to nuclear-weapon-free zones, there are treaties and declarations, which are not covered by this fact sheet, banning the deployment of nuclear weapons in Antarctica, Mongolia, on the seabed, and in outer space.
Basic Elements of Nuclear-Weapon-Free Zone Treaties
Duration: The treaties are to remain in force indefinitely. Yet, each treaty includes a withdrawal option for states-parties. With the exception of the Treaty of Tlatelolco, which simply requires three months' advance notice before a withdrawal can take effect, all the NWFZ treaties require 12 months' advance notice for a state-party to end its treaty obligations.
Conditions: None of the treaties can be subjected to conditions by its non-nuclear-weapon states-parties.
Verification: Each state-party adopts comprehensive safeguards administered by the International Atomic Energy Agency (IAEA), which verifies that states-parties are not pursuing nuclear weapons illicitly. The Central Asian NWFZ goes a step further in requiring that states in the region adopt the IAEA's Additional Protocol, which provides for expanded monitoring.
Territory Covered: Each zone applies to the entire territories of all of its states-parties. Territory is understood to include all land holdings, internal waters, territorial seas, and archipelagic waters. The Latin American treaty also extends hundreds of kilometers from the states-parties' territories into the Pacific and Atlantic Oceans, but the nuclear-weapon states, citing their freedom at sea, assert that this does not apply to their ships and aircraft that might be carrying nuclear weapons. A dispute also exists over the inclusion of the Chagos Archipelago, which includes the U.S. military base at Diego Garcia in the Indian Ocean, as part of the proposed African nuclear-weapon-free zone. Neither the United States nor the United Kingdom recognizes Diego Garcia as being subject to the Pelindaba Treaty.
Initial efforts to create an area free of nuclear weapons began in the late 1950s with several proposals to establish such a zone in Central and Eastern Europe. Poland offered the first proposal-named the Rapacki Plan after the Polish foreign minister-in 1958. The Rapacki Plan sought to initially keep nuclear weapons from being deployed in Poland, Czechoslovakia, West Germany, and East Germany, while reserving the right for other European countries to follow suit. The Soviet Union, Sweden, Finland, Romania, and Bulgaria also floated similar proposals. All these early efforts, however, floundered amidst the U.S.-Soviet superpower conflict, although the Rapacki Plan would serve as a model to the nuclear-weapon-free zones that were eventually set up in other regions of the globe.
The Treaty of Tlatelolco (Latin America and the Caribbean)
Opened for signature: February 14, 1967
Entered into force: October 23, 2002
States-parties: 33 total; Antigua and Barbuda, Argentina, Bahamas, Barbados, Belize, Bolivia, Brazil, Chile, Colombia, Costa Rica, Cuba, Dominica, Dominican Republic, Ecuador, El Salvador, Grenada, Guatemala, Guyana, Haiti, Honduras, Jamaica, Mexico, Nicaragua, Panama, Paraguay, Peru, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and Grenadines, Suriname, Trinidad and Tobago, Uruguay, and Venezuela.
Protocol ratification by nuclear-weapon states: Protocol II (negative security assurances) ratified by China, France, the United Kingdom, the United States, and the Soviet Union.
The Treaty of Rarotonga (South Pacific)
Opened for signature: August 6, 1985
Entered into force: December 11, 1986
States-parties: 13 total; Australia, Cook Islands, Fiji, Kiribati, Nauru, New Zealand, Niue, Papua New Guinea, Samoa, Solomon Islands, Tonga, Tuvalu, and Vanuatu.
Protocol ratification by nuclear-weapon states: Protocol I (prohibition on the manufacture, stationing and testing of any nuclear explosive device - open only to France, the United Kingdom and the United States) ratified by France, and the United Kingdom. Protocol II (negative security assurances) ratified by China, France, the United Kingdom, and the Soviet Union. Protocol III (ban on nuclear testing in the nuclear-weapon-free zone) ratified by China, France, the United Kingdom, and the Soviet Union.
The Treaty of Bangkok (Southeast Asia)
Opened for signature: December 15, 1995
Entered into force: March 27, 1997
State-parties: 10 total; Brunei Darussalam, Cambodia, Indonesia, Laos, Malaysia, Myanmar, Philippines, Singapore, Thailand, and Vietnam.
Protocol ratification by nuclear-weapon states: None. Five nuclear weapons states and ASEAN members met in July 2012 to sign the treaty protocol. The treaty commission, however, postponed the signing of the protocol until November, requesting more time to review reservations that several of the NWS indicated that they would attach during ratification.
The Treaty of Pelindaba (Africa)
Opened for signature: April 11, 1996
Entered into force: July 15, 2009
States-parties: 28 total; Algeria, Benin, Botswana, Burkina Faso, Burundi, Cote d'Ivoire, Equatorial Guinea, Ethiopia, Gabon, Gambia, Guinea, Kenya, Lesotho, Libyan Arab Jamahiriya, Madagascar, Malawi, Mali, Mauritania, Mauritius, Mozambique, Nigeria, Rwanda, Senegal, South Africa, Swaziland, Togo, United Republic of Tanzania, and Zimbabwe. Signatories that have not ratified the treaty are: Angola, Cameroon, Central African Republic, Cape Verde, Chad, Comoros, Congo, Djibouti, Democratic Republic of Congo, Egypt, Eritrea, Ghana, Guinea-Bissau, Liberia, Niger, Seychelles, Sierra Leone, Somalia, Sao Tome & Principe, Sudan, Tunisia, Uganda and Zambia, as well as the area known as the Sahrawi Arab Democratic Republic.
Protocol ratification by nuclear-weapon states: Protocol I (negative security assurances) ratified by China, France, Russia, and the United Kingdom. Protocol II (ban on nuclear testing in the nuclear-weapon-free zone) ratified by China, France, Russia, and the United Kingdom.
Central Asian Nuclear-Weapon-Free Zone Treaty
Opened for signature: September 8, 2006
Entered into force: March 21, 2009
States-parties: 5 total; Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan.
Protocol ratification by nuclear-weapon states: Protocol I ratified by France and the United Kingdom. At the 2015 NPT Review Conference, the United States and Russia announced that they submitted the protocols for ratification.
1. The treaty specified that the full zone would not enter into force until it was ratified by all states within the zones. That did not occur until Cuba ratified the treaty in 2002. However, the treaty permitted individual states to waive that provision and declare themselves bound by the treaty, which many did beginning in 1968.