Skip to content

November 7, 1967

25th Meeting of Non-Aligned Group with Discussion on Peaceful Nuclear Explosions

This document was made possible with support from Carnegie Corporation of New York (CCNY)

Date: 1 November, 1967 – 25th meeting of Non-Aligned Group

Date of letter: 7 November 1967



A brief and interesting discussion then took place between the delegations of Brazil and Mexico as to whether or not PNEs [peaceful nuclear explosions] were permitted under the LANWFZ [Treaty for the Prohibition of Nuclear Weapons in Latin America and the Caribbean]. The reps of Br and MX reaffirmed their respective interpretations of the LA treaty, particularly its articles I, 5 and 18. This discussion also included an exchange of views on what was meant by the expression used in the draft resolution jointly sponsored by 21 LA countries at the current session of the UNGA, which referred to the right of the LA countries to use nuclear energy “for demonstrated peaceful purposes.” The Brazilian and the Mexican representatives clashed on the interpretation of this term, particularly on the issue whether it permitted or prohibited the conduct of PNEs by LA countries. Castaneda of Mexico said that a PNE was a “canister,” which was roughly three feet in diameter and six feet in length. Although its shape and outer shell were different from those of a nuclear weapon and it did not possess certain characteristics which were essential in a weapon, the “canister” was still no different from a bomb. Silveira, on the other hand, took the line that the crux of the matter was really that of the control of peaceful nuclear explosions. The technology of making and using peaceful nuclear devices could not any longer remain hidden from the scientists of the developing countries. What should, therefore, be ensured was proper regulation of the manufacture and use of nuclear explosives rather than their denial to non-nuclear-weapon countries under a non-proliferation treaty. Castaneda replied that any system of controls, howsoever elaborate, could not prevent a possible misuse of a canister which was for all intents and purposes a bomb. Colonel Boman agreed with the Mexican point of view and said that the canisters could definitely be used as nuclear mines in a situation like that envisaged by the Government of Turkey in their proposal recently submitted to the nuclear planning group – the McNamara Committee – of the NATO. Silveira then referred to the report which had appeared in the New York Herald Tribune on the 1st of November, in which it was stated that a nuclear expert of a nuclear energy corporation of Las Vegas, Dr. Coffer, had estimated that something like 1,000 PNEs would be needed in the US alone to tap its hitherto inaccessible natural resources buried deep underground and for other peaceful purposes. Silveira argued that against the background of this report, the requirements of the developing countries for this technology could very well be visualized and that in such a situation the only answer to the problem was not to deny the technology to the developing countries but to permit its full development – of course, under proper regulation. Castaneda said that the analogy in the situations regarding the peaceful uses of nuclear devices between the NWPs and NNWPs was not quite correct, as it did not take into account the significant fact that the control of the devices would in the former case be firmly in the hands of the Governments of the NWPs. The explosions would be conducted under the auspices of the Government of a nuclear weapon power and only after the required cool-off period had elapsed, the work of exploitation of natural resources or a civil engineering project would be made the responsibility of a private corporation. Castaneda repeated his contention that controls did not provide the answer for all possibilities and that if a non-nuclear country were allowed to develop a device, it was being allowed the possibility of having a bomb.



Mexican and Brazilian representatives disagree on if peaceful nuclear explosions (PNEs) are allowed by the Latin American treaty.


Document Information


File No. HI/1012(48)/67. Obtained by Ryan Musto.

Original Archive


The History and Public Policy Program welcomes reuse of Digital Archive materials for research and educational purposes. Some documents may be subject to copyright, which is retained by the rights holders in accordance with US and international copyright laws. When possible, rights holders have been contacted for permission to reproduce their materials.

To enquire about this document's rights status or request permission for commercial use, please contact the History and Public Policy Program at [email protected].

Original Uploaded Date



Record ID


Original Classification



Carnegie Corporation of New York (CCNY)