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Nuclear Weapon Free Zones and Denuclearization

Nuclear Weapon Free Zones and Denuclearization

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Emblem of the Antarctic Treaty

Since nuclear weapons were first used in August 1945, the international community has made great strides to limit the development and deployment of nuclear weapons. Numerous treaties prohibit the testing and deployment of nuclear weapons in specific areas, such as outer space. Additionally, the United Nations recognizes five regions as Nuclear Weapon Free Zones (NFWZ). 

Nuclear Weapon Free Zones (NWFZ)

The United Nations defines a Nuclear Weapon Free Zone as, “any zone recognized as such by the General Assembly of the United Nations, which any group of States, in the free exercises of their sovereignty, has established by virtue of a treaty or convention whereby: (a) The statute of total absence of nuclear weapons to which the zone shall be subject, including the procedure for the delimitation of the zone, is defined; (b) An international system of verification and control is established to guarantee compliance with the obligations deriving from that statute.”

Treaty of Tlatelolco: The Treaty of Tlatelolco established Latin America as an NWFZ. It opened for signature on February 14, 1967. Twenty-one Latin American states signed the treaty before the end of the year. Cuba was the last Latin American state to sign in March 1995. 

Treaty of Rarotonga: The South Pacific Nuclear Free Zone Treaty, also known as the Treaty of Rarotonga, established an NWFZ in much of the South Pacific. It was signed in August 1985 by Australia and seven island states. Three others joined within the next two years. In the mid-1990s Vanuatu and Tonga joined the NWFZ.

Treaty of Bangkok: On December 15, 1995, ten states in Southeast Asia signed the Treaty on the Southeast Asia Nuclear Weapon-Free Zone in Bangkok, Thailand. The treaty entered into force in March 1997.

Initial talks to establish an NWFZ began in 1971. However, internal and external political tensions prevented an agreement until the mid-1990s.

Treaty of Pelindaba: The African Nuclear Weapon Free Zone Treaty or Treaty of Pelindaba opened for signature on April 11, 1996. The Treaty entered into force on July 15, 2009. As of 2017, 52 African states had signed the treaty, and 41 had ratified it.

Treaty on a Nuclear-Weapon-Free Zone in Central Asia (CANWFZ): On September 8, 2006 the five states of Central Asia—Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan—signed the CANWFZ Treaty.

Groundwork for the NWFZ began in 1992 after Mongolia declared itself an NWFZ and called on other states within the greater region to follow suit. In 1993, Uzbek President Islam Karimov made the first formal proposal for a CANWFZ. In 1997 all five Central Asian heads of state endorsed the creation of a CANWFZ. By fall 2002, the states reached a preliminary agreement. 

Other Denuclearization Treaties

Antarctic Treaty: The Antarctic Treaty was signed on December 1, 1959 by twelve states including Russia, the United States, and the United Kingdom. It went into effect on June 23, 1961.

The treaty stipulates that Antarctica could only be used for peaceful purposes. Article 5 of the treaty bans the testing of nuclear weapons and disposal of radioactive waste in Antarctica. 

Outer Space Treaty and the Moon Agreement: The Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space or, more simply, the Outer Space Treaty, prohibits signing parties from placing any objects carrying a nuclear weapon or other weapons of mass destruction into orbit around the Earth. The treaty opened for signature on January 27, 1967 and entered into force on October 10, 1967. There are currently over one hundred parties to this treaty.

The Moon Agreement, which entered into force on July 11, 1984, reaffirmed and elaborated on certain provisions of the Outer Space Treaty, stating formally that the moon and other celestial bodies were to be used for peaceful purposes only. It required states to inform the United Nations of any station on celestial bodies included in the agreement.

Seabed Treaty: The Treaty on the Prohibition of the Emplacement of Nuclear Weapons and Other Weapons of Mass Destruction on the Sea-Bed and the Ocean Floor and in the Subsoil Thereof—or simply the Seabed Treaty—prohibits the placement of nuclear weapons or other weapons of mass destruction on the seabed and the ocean floor beyond a 12-mile coastal zone.

The treaty opened for signatures on February 11, 1971 and entered into force on May 18, 1972.