Treaty of Tlatelolco

A visual illustration of the Nuclear-Weapon-Free Zone in Latin America and the Caribbean

Visual illustration of the NWFZ in Latin America and the Caribbean

Image source: OPANAL


The Treaty for the Prohibition of Nuclear Weapons in Latin America and the Caribbean (Treaty of Tlatelolco) was opened for signature on 14 February 1967 in Mexico City.

Article 4 of the Treaty of Tlatelolco delineates its Zone of Application as the whole of the territories for which the Treaty is in force.

The Zone of Application defined by the Treaty of Tlatelolco encompasses a surface of more than 20 million square kilometers. It includes areas of the high seas, defined by the United Nations Convention on the Law of the Sea , and the national territories of the 33 countries of Latin America and the Caribbean, home to more than 600 million people. The Treaty of Tlatelolco does not extend nor does claim sovereignty of the aforementioned high seas regions for the States Parties, it establishes them as nuclear-weapon-free in accordance with Additional Protocol II of the Treaty.

Full text of the Tlatelolco Treaty is available at the UN Disarmament Treaties Database:



The current States Parties to the Treaty are: 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, St. Kitts and Nevis, St. Lucia, St. Vincent and the Grenadines, Suriname, Trinidad and Tobago, Uruguay, Venezuela.


Internal Coordination Mechanisms

In order to ensure compliance with the obligations of the Treaty of Tlatelolco, the Contracting Parties established in 1969 the Agency for the Prohibition of Nuclear Weapons in Latin America and the Caribbean (OPANAL).

The Agency is responsible for holding meetings among Member States related to the purposes, provisions and procedures established by the Treaty.

The Treaty of Tlatelolco establishes the General Conference, the Council and the Secretariat as principal organs of OPANAL. The Secretary-General is the highest officer of the Secretariat.

By provision of Article 7 of the Treaty of Tlatelolco, OPANAL headquarters is located in Mexico City.

The General Conference is the supreme organ of OPANAL, is composed of all the Contracting Parties, namely, all the 33 Latin America and the Caribbean countries; it holds regular meetings every two years and may also hold special sessions whenever the Treaty of Tlatelolco so provides or, in the opinion of the Council, the circumstances so require.

Among the faculties of the General Conference include:

  • Analysis and decision on any matters or questions covered by the Treaty of Tlatelolco, including those referring to powers and functions of any organ provided in the Treaty;
  • Establishing procedures for the Control System to ensure observance of the Treaty of Tlatelolco;
  • Elect the Members of the Council and the Secretary General;
  • May remove the Secretary General from office;
  • Initiate and consider studies designed to facilitate the optimum fulfillment of the aims of the Treaty, without prejudice to the power of the Secretary General;
  • Is the organ competent to authorize the conclusion of agreements with Governments and International Organizations;
  • Adopts the Agency’s budget and fix the scale of financial contributions to be paid by Member States;
  • Elects its officers for each session and may establish such subsidiary organs as it deems necessary;