This memorandum is a compendium of comments about the Treaty of Tlatelolco made by different delegations at the UN. It includes statements by the delegates from the United States, Brazil, Ireland, Ethiopia, Austria, Italy, Pakistan, El Salvador, Mauritania, Iraq, Greece, Spain, Tanzania, Zambia, the Netherlands, Argentina, Venezuela, Sierra Leone, Canada, Jordan, Ecuador, Guyana, Colombia, Malta, Panama, Bolivia, Costa Rica, and Peru, in that order.

Alfonso Garcia Robles explained Mexico’s position toward the proliferation of nuclear weapons, the Mexican delegation’s position toward the NPT draft, and a comparison between the Treaty of Tlatelolco and the NPT draft. He explained that the Mexican delegation favored the NPT draft but wanted to make minor language modifications and include an explicit reference to the UN Charter’s articles on the use of force, especially Articles 2 (IV) and 26. Garcia Robles also explained why he thought the Treaty of Tlatelolco was “superior” to the NPT draft as a response to nuclear risks. He argued that the regional treaty better addressed nuclear threats than the NPT draft because it included more constraints on nuclear powers, a more precise definition of a nuclear weapon, and a more institutionalized system of controls.

Alfonso Garcia Robles explained how the Mexican delegation tried to gather the support of the Latin American countries for the NPT draft. These countries prepared and presented modifications to the NPT text, and the United States and the Soviet Union accepted some of these proposals. Garcia Robles reported that the Argentinian and Brazilian representatives said they recognized the value of the NPT but would not support it if it kept its clause prohibiting peaceful nuclear explosions. The Ambassador also reported the Soviet positive reactions toward the Treaty of Tlatelolco. Garcia Robles recounted the skepticism of some delegations toward the NPT. He recommended not to sign the NPT in 1968 unless the Soviet Union signed Protocol II of the Treaty of Tlatelolco, which includes negative security assurances.

Alfonso Garcia Robles announced the success of the negotiations drafting the Treaty of Tlatelolco and its opening for signatures. He recounted the expressions of support and admiration for the treaty from different authorities, especially from U Thant, the UN Secretary-General, who hoped the Treaty of Tlatelolco would serve as an example and an impetus for similar efforts. He also explained that the Treaty of Tlatelolco managed to balance two fundamental goals: preventing the proliferation of nuclear arsenals and guaranteeing access to peaceful uses of nuclear technologies.

Alfonso Garcia Robles used his address to describe the progress in the negotiations of the Treaty of Tlatelolco. For him, this treaty included the most ambitious definition of nuclear weapons compared to existing nuclear governance texts. Another innovation was the reliance on the International Atomic Energy Agency’s safeguard system to monitor compliance. Garcia Robles also explained that Latin American delegations were almost in consensus about the Treaty of Tlatelolco text except for a couple of issues. Countries did not agree on defining the territory where the treaty would apply and when it would enter into force. The Ambassador also took this opportunity to explain the Latin American efforts to obtain negative security assurances from China. Moreover, he reminded delegates that the success of the NPT would depend on balancing obligations for nuclear and non-nuclear-weapon states. Mexican representatives argued that it was necessary to include more ambitious disarmament goals in the draft of the NPT. However, they rejected proposals to condition the approval of the NPT on the existence of concrete steps toward disarmament

The president of the Mexican delegation to the United Nations (UN), Ambassador Alfonso Garcia Robles, explained why the Latin American nuclear-weapon-free zone (NWFZ) would represent the most ambitious regional project to address nuclear perils. He explained the security implications of the agreement, especially in terms of nuclear nonproliferation, nuclear disarmament, and negative security assurances. He also clarified that the Latin American project would benefit signatories economically. He argued that Latin American governments would not have to waste the resources necessary to engage in nuclear arms races if the region were denuclearized. Moreover, he explained that Mexico’s final aim was to achieve general and complete disarmament; thus, Mexican authorities saw the NPT as a means and not a goal on its own.