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June 22, 1966

Note on the Third Session of the Preparatory Commission for the Denuclearization of Latin America held in Mexico City from April 19 to May 4, 1966

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

TITLE: A Note on the Third Session of the Preparatory Commission for the Denuclearization of Latin America held in Mexico City from April 19 to May 4, 1966.

Prepared By: K.C. Jain, First Secretary (Disarmament)

DATE: June 22, 1966


The Preparatory Commission which was set up in pursuance of the UN resolution 1911 (XVIII) to prepare a treaty for the denuclearization of Latin America, held its third session in Mexico City from April 19 to May 4, 1966. A document, called the “Final Act” of the session, has been circulated at the request of the President of the Preparatory Commission as a UN General Assembly document (A/6328). This document contains the texts of all the seven resolutions adopted by the Commission, including the text of a draft treaty on the denuclearization of Latin America, as it emerged at the end of the third session.


2. The Latin American countries may perhaps legitimately take pride in the fact that although various proposals have been made during the last few years to create denuclearized zones in different parts of the world as a means of limiting the nuclear arms race and also checking to some extent the proliferation of nuclear weapons, the Latin Americans alone have gone into the question of a denuclearized zone for their own region in a very serious and detailed manner. They alone have set up a Preparatory Commission to prepare a legal instrument for the purpose, have for the first time clarified the issues and defined the various terms and concepts (including the term “nuclear weapons”) and have even drawn up a draft treaty. As has been claimed, 90 percent of the articles of this draft treaty have already been agreed upon unanimously. It would, however, not be safe to conclude that a treaty is round the corner and that a pioneering attempt on a regional basis in the field of disarmament is about to succeed. An effort has been made in the following paragraphs to bring some of the main issues involved in a clearer focus.


Preparation of the Draft Treaty


When the third session of the Preparatory Commission began in Mexico, the Coordinating Committee submitted a draft of the treaty for the denuclearization of Latin America. The Brazilians objected to the draft on the ground that the Coordinating Committee was not competent to submit a draft and as such the Coordinating Committee’s draft had no legal status. Brazil, therefore, submitted its own draft which incorporated large portions of the Coordinating Committee’s draft and gave its own reformulations of all such articles on which it differed from the Coordinating Committee. Two days after the submission of this alternative draft by Brazil, Colombia became its co-sponsor. Then the Coordinating Committee draft and the Brazilian-Colombian draft were placed side by side and a joint document was drawn up, which retained the articles which were common to both the drafts and in regard to such articles where there was a divergence, the two versions were reproduced side-by-side – the version on the left being that of the Coordinating Committee (with which Mexico, Chile, Ecuador and El Salvador were in agreement), the version on the right representing the views of Brazil, Colombia, Venezuela, and Argentina. The bracketed portions indicate the divergence between the two versions.


Tello disclosed to me that the Brazilians, the excellent diplomats that they were, remained in the background and were very suave and pleasant. They left the dirty work of arguing and wrangling to be done by the Argentinians and the Venezuelans who proved to be the most difficult to negotiate with.


The draft treaty on the denuclearization of Latin America which is reproduced as an Annex to resolution 14 of the Third Session of the Prep Comm contains a preamble, 26 articles and has two annexures. The crucial article in the treaty is article 23 which refers to entry into force of the treaty. As in the case of the other articles in regard to which there are alternative texts, this article also has a text on the left hand side which represents the Mexican-Chilean approach and the text on the right which represents the Brazilian-Colombia-Argentine approach.


The Rival Mexican and Brazilian Approaches


The Mexican-Chilean view is that the treaty could come into force once 11 states had ratified the treaty or acceded to it. (Earlier, they had suggested that five countries were enough for a denuclearized zone to be established in Latin America. They have now as a compromise to the Br-Ar-Co approach raised the number to 11 and believe that a compromise could perhaps be struct with the latter’s approach of unanimity or universality by agreeing to the figure of the two-thirds of the Latin American states which would be 14 out of 21). The Brazilians consider that all states without exception in the region of Latin America should agree to abide by the Treaty. All the nuclear powers should guarantee the status of the zone as protocol I to the treaty and all states which have de jure or de facto responsibility for administration of territories south of latitude 30 degrees North should abide by the same commitments as are being proposed for the sovereign countries of Latin America. Both these protocols are reproduced at Annexure II of the Treaty.


The Mexicans consider that a General Assembly resolution would be adequate for bringing in the nuclear powers to “refrain from taking, directly or indirectly, for whatever reason, any action that might jeopardize faithful compliance with the provisions of the Treaty.” (A draft of this resolution is at Annexure I to the draft treaty). They argue that the question of respecting the status of Latin American countries by other countries, including even nuclear powers, does not arise. The UN Charter specifically provides that all countries will respect each other’s sovereignty. Thus the nuclear powers have no right to introduce nuclear weapons into any country of Latin America against its will. All that therefore the Latin Americans can ask is that the nuclear powers should refrain from taking any action that might jeopardize faithful compliance by the Latins themselves with the provisions of the Treaty. As for the argument that China being not a member of the United Nations would not be considered bound by a UN Resolution, the Mexicans argue that they have made a provision in this resolution for a country subsequently acceding to it, whereby the Chinese could accede to this resolution at a later date when they became a member of the United Nations. Alternatively, the Chinese could issue a separate declaration on similar lines as the General Assembly resolution.


The Mexicans say that the Brazilian approach was greatly influenced by their thinking that if Cuba did not sign the treaty, they would not sign it too. The Mexicans argue that this was not a correct position to take because all the Latin Americans with the exception of Mexico have ostracized Cuba. Mexico is the only country in Latin America which has diplomatic relations with Cuba. For the Brazilians, therefore, to expect that the moment a denuclearized treaty was signed, Cuba should accede to it was completely unrealistic. The Mexicans argue that their approach to the question of denuclearization of Latin America was a pragmatic one, because once 11 or 14 countries signed the treaty, a momentum would develop and other countries would also join in. The Mexicans are confident on the basis of their informal soundings with the Cubans that they would be able to persuade Cuba to join in after two or three years. (One cannot take this Mexican claims at its face value. It may well be a ruse on their part to persuade Brazil and other like-minded Latin American states to join in).


As for the argument that the Mexican approach will result in patches of denuclearized territories in Latin America, the Mexicans refer to the Kosygin proposal and say that the fact that the Soviet Union was prepared to guarantee the security of any country that decided to stay non-nuclear and did not have nuclear weapons on its territory showed that any country could declare itself to be a denuclearized zone. Therefore, even if there was no geographical contiguity between the 11 or 14 countries which may decide to sign a treaty, and they might not qualify themselves to be called a denuclearized Latin American zone, they would be perfectly entitled to call themselves as signatories to the Treaty on the Denuclearization of Latin America. The Mexicans believe that the passage of time will surely convince the doubting states of the utility of the movement for a denuclearized zone in Latin America to be established with a few signatories to being with.


The Brazilian approach is based on the thesis that denuclearized zones were really needed only so long as the non-proliferation treaty was not signed. Once a non-proliferation treaty had been signed, the denuclearized zones would lose their raison d’etre. A denuclearized zone is a partial non-proliferation measure and there is a need for great vigilance in the absence of a non-proliferation treaty. All countries, without exception, in a region which is proposed to be denuclearized must join in the arrangement, otherwise such an arrangement would do more harm than good. Brazilians consider that their approach was based on common-sense and a realization that their experiment in Latin American would have far-reaching repercussions all over the world. For example, how could the countries of Africa be expected to join a treaty on the denuclearization of their region, if South Africa chose to remain outside such an arrangement. The position would obviously be fraught with serious dangers. Or, how could there be a denuclearized in the region of Asia and the Pacific without China undertaking the obligations which other countries in that region would be taking upon themselves.


Future Prospects


As regards the prospects for the forthcoming session of the Preparatory Commission, the Brazilians are convinced that their approach was bound to prevail ultimately for there could be no compromise on fundamental principles. The Brazilians argue that if it came to a showdown the Mexicans would not get even 11 countries to agree to their conception of a denuclearized zone in Latin America and whatever countries would join in would not be of much political or military significance. The Mexicans could get some Central American states and one or two others. After all, Brazil, Colombia, Argentina, Venezuela, and Uruguay would not join such an arrangement.


If there is a change of the Government of Cuba, it is possible that eh Cuban attitude to the question of denuclearization of Latin America may change. The United States has already offered to include their Guantanamo base in the arrangement if Cuba adhered to the Treaty.


The Mexicans are of course very confident that they would have a treaty this year. They are hopeful that 11 or 14 countries may sign it. It is however difficult to share their optimism, because when the third session of the Preparatory Commission met, the Latin American countries were only aware of the Coordinating Committee draft, which was in effect the Mexican draft. Their delegations to the Third Session had received instructions on the basis that there was going to be only one draft. The Brazilian-Colombian draft came later, after the conference had started. Now that the Brazilian position has been so clearly stated, it is doubtful whether the other Latin American countries would like to cause any affront to the Brazilians who are the biggest factor in Latin America.



Motivations Behind the Mexican and Brazilian Approaches


The Brazilian view is that the motivation behind the Mexican approach is either idealism or a desire for glory. The Brazilians were the first to propose the establishment of such a zone for Latin America. They did it in 1962. The General Assembly resolution 1911 (XVIII) was adopted in 1963, as a result of which the present Preparatory Commission was established.  The Brazilians say that they have since realized that the problem was full of implications and complications and that there was need for great caution. That is why the Brazilians insist that the question of entry into force of the treaty was a vital matter. A General Assembly resolution would be too weak a method for securing the commitments of all the nuclear powers and the states which had de jure and de facto responsibility for administration of territories in Latin America. There would have to be legal documents whereby such states should undertake solemn obligations. These legal obligations could be in the form of two protocols of guarantees, as proposed by them in Annexure II of the draft treaty, as it has been developed by the third session.


The Mexican representative at the Eighteen-Nation Conference in Geneva has in his statement of the 14th of June very cleverly and significantly expressed the Mexican point of view by saying that there was’ the absolute right of any regional group to constitute within itself entirely denuclearized zones.” (ENDC/PV. 264, lines 12 and 13). This is a clear reiteration of the Mexican approach that there need not necessarily be only one denuclearized zone within a regional group but that there could be several such zones.


The Mexicans have made this question an issue of high prestige. Their two Presidents have been personally dedicated to this idea. A Mexican representative, Ambassador Robles, is the chairman of the Preparatory Commission. There is also an element of rivalry and jealously in this matter. Another reason of the difference of opinion is the honest ideological one. The economic issue is also involved. The Mexicans do not want to spend anything on nuclear weapons whatever happens.


The Mexican approach is to a very large extent governed by the fact that the Mexican security has been regarded by United States policy makers as matter of their direct concern. Whether Mexico wants it or not, their security is taken care of by the Americans. A Mexican General told Diesel that Mexico had the biggest and strongest army in the whole world, but Mexico preferred to station it north of the Rio Grande. The Mexicans, therefore, are determined not to waste any of their resources on defence, particularly nuclear defence. They are determined that they would not and need not go in for nuclear weapons because the United States in the interest of its own Security would have to see to it that no harm came to Mexico. No wonder then that Mexico does not bother about the possibility of any nuclear danger from Cuba.


The Brazilians have to look at the problem differently. They feel that their security is their own concern, that they have to be self-reliant because they cannot, like Mexico, depend on the United States for their security. Besides, Brazil is the largest country in Latin America, a country which is even larger in size than the United States. Brazil is also conscious of its predominant position in the region.


It can be concluded that when the Mexicans claim – Robles said so in Mexico and Robledo repeated it in Geneva – that 90% agreement had been reached on the draft treaty, they are correct in so far as the number of articles in the draft treaty was concerned. It is also true that it is only in regard to a few articles, which would be 10% of the whole treaty, that there is at present a difference of opinion, but this 10% is the crux of the whole matter. Fundamental differences are involved and there is no possibility of yet another compromise emerging in this area of difference, unless either Mexico or Brazil changes its basic stand. If the Mexicans went ahead with their conception of establishing a zone with whosoever were willing to join, there would be an unreal zone in which the big countries like Brazil and Argentina would not participate. If the Brazilians stuck to their guns, a denuclearized Latin America would exist only on paper.


One of the questions that was informally discussed among some of the delegates and observers in Mexico City was: how the Brazilian attitude in Geneva could be reconciled with the Brazilian attitude in Mexico. How was it that in Geneva the Brazilians were one of the softest, while in Mexico they were one of the hardest. It was generally felt that the most logical explanation of this divergence of approach of Brazil was that in Geneva they worked in a world-wide framework. Besides, they considered that a non-proliferation treaty had to be seen in the global setting. In Mexico, they were working in the Latin American context, where they had to be particularly careful about their own security. The fact that the military was in power in Brazil explained to no small extent the Brazilian insistence on an appropriate and safeguarded legal instrument for a renunciation of nuclear weapons. An influential member of the Brazilian delegation, Antonio Bueno, told Diesel that Brazil would like to keep the nuclear option open unless and until an arrangement which was satisfactory from the point of view of the Brazilian security was arrived at in regard to Latin America.


The question of transit of nuclear weapons through the territory of the States joining the proposed denuclearized zone in Latin America.


An interesting question has been raised by Nicaragua regarding the question of transit of nuclear weapons through the territory of a Latin American state, which may join a treaty on the denuclearization of Latin America. This question is reflected in page 9 of the Final Act and Article IB of the draft treaty.


Although the word transit has not been spelt out, there has been speculation that it could mean either air transit or trans through a canal like the Panama Canal. Nicaragua has argued that a sovereign country has the right to decide whether it should allow the transit of nuclear weapons through its territory. A denuclearization treaty should not prohibit such transit. An instance where such a situation could raise would be if there were two US aircraft carriers, one in the Pacific and the other in the Atlantic, and the aeroplanes from one of these aircraft carriers were required by the US Government to fly nuclear weapons to the other aircraft territory of one of the Latin American signatories to the treaty. In such a situation, a country like Mexico may decide not to permit the flight of such an aircraft. On the other hand, a country like Nicaragua, may under certain circumstances decide to allow such an overflight to take place. The Nicaraguans were the only country which insisted that such an eventuality should be taken care of in the draft treaty. The left side version of article IB reflects the Nicaraguan approach. The right side version represents the approach of the rest of the Latin Americans. This sub article therefore has a difference of opinion of 1:20 in the 21 member conference of the Latin American states. The Mexicans think that this divergence could be taken care of by a prohibition of “transport” of nuclear weapons, which would mean only overland transport would be prohibited and not air or canal transit.


In regard to the question of transit of nuclear weapons through a canal, it may well be asked why Panama itself did not raise this question as it is the only country which could be said to be at present concerned with this issue. Diesel told me that the Panamanian representative did not openly support the Nicaraguan proposal because he could not receive instructions in time from his Government in regard to the proposal, which had been made rather late in the session. However, he did show his sympathy towards the proposal. As there has been a talk of building a canal similar to the Panama Canal through the Nicaraguan territory, the Nicaraguans may also have had this possibility in mind when putting forward their proposal that transit of nuclear weapons should not be specifically forbidden by the Treaty.


Definition of the Zone


The representative of Uruguay raised the question of fixing the exact limits of the zone. He suggested that not only should the geographical frontiers of the zone be demarcated but elements like the territorial waters and air space should also be clearly defined. As is well-known, one element in this question would be the fact that Chile, Ecuador, and Peru claim a 200-mile sovereignty over territorial waters while the other States claim from 3 to 12 miles. Discussions were, however, inconclusive on this question and it was decided that Governments should study the Uruguayan proposal carefully.


Creation of denuclearized zones in other regions of the world


In the initial draft submitted by Brazil and Colombia (as also in the Coordinating Committee draft prepared on the basis of Mexican thinking), the preamble to the draft treaty contained the following sentence regarding the significance of the experiment in Latin America for the creation of denuclearized zones in other regions of the world:



That the denuclearization of vast geographical areas, adopted by the sovereign decision of the States comprised therein, will exercise a beneficial influence on other regions.”


Diesel pointed out to the Brazilian Ambassador Sette Camara that this formulation could put West Germany in an embarrassing position vis-à-vis the Soviet Union who had been supporting the Polish demand for the creation of a denuclearized zone in Central Europe. He, therefore, suggested to him that the words “where similar conditions exist” should be added to the above sentence. Diesel stressed this amendment suggested by him was not a mere formality but a very substantial matter. Diesel told me that Camara was quick to see the point and himself proposed the amendment, which was accepted by the Preparatory Commission. (This amended sentence stands at the top of page 15 of the UNGA Document A/6328). Diesel said that when the Argentineans came to know about this they came to him and told him that they would like him to convey to his Government that they were not aware of the German wishes earlier but had they been asked to propose the amendment, they would have been only too happy to do themselves.


Contacts with the People’s Republic of China regarding an undertaking to respect the legal instrument on the denuclearization of Latin America.


The third session of the Prep Comm has by its resolution 12(III) requested its Negotiating Committee “to make informal inquiries in the manner and the means it deems fit to ascertain whether the Government of the People’s Republic of China would be prepared to undertake to respect the legal instrument on the denuclearization of Latin America.” The Negotiating Committee consists of representatives of Brazil, Mexico and Ecuador.


It is not yet known in what manner the contacts with the Chinese government are to be made. Three possibilities have been mentioned. The second possibility is generally believed to be the most likely one. I) The Negotiating Committee might decide to send a representative to Peking to ascertain the attitude of the Chinese government. II) The contacts may be established at the ambassadorial level in a country where China as well as all the three Negotiating Committee countries have embassies. There has been some speculation that Paris may perhaps be the most likely venue of such a meeting as the Chinese have a full-fledged ambassador  there and the Latins also have very strong representation. III) The Chinese might send an observer at the 4th Session of the Preparatory Commission due to being in Mexico on the 30th of August, 1966. (The Mexicans have mentioned this possibility on the basis that the official New China News Agency (NCNA) had spent two of its journalists to cover the third session of the Preparatory Commission).


Tello said that the American delegation in Geneva have evinced keen interest in finding out from the Mexican delegation as to know how the informal inquiries envisaged in resolution 12 (III) of the Preparatory Commission are to be instituted with the People’s Republic of China. The new deputy chairman of the US delegation, George Bunn, is himself making inquiries about the way these contacts are proposed to be established by the Negotiating Committee with the Chinese. (Incidentally, Bunn is one of the two or three men who had drafted the charter of the US Arms Control and Disarmament Agency and is one of the cleverest back-room boys in the United States policy-making echelons and is a close confidant and adviser of Foster).


The Mexicans are very hopeful that the Chinese could be persuaded to respect the legal instrument on the denuclearization of Latin America. They argue that their optimism is based on the following grounds: i) Immediately after their first nuclear test explosion of October 16, 1964, the Chinese had declared that they would not be the first to use nuclear weapons. II) The door has been opened for the Chinese to prove their bonafides in this regard by respecting the legal instrument on the denuclearization of Latin America. III) In view of the persistent Latin American vote against the Chinese admission to the United Nations, the Chinese would like to earn the goodwill of the Latins by accepting their request and thus secure a propaganda advantage. They might even ask for Latin American support for their admission to the United Nations in return for guaranteeing their status as a denuclearized zone.


A guarantee by China to respect the status of the proposed denuclearized zone in Latin America does not cost anything to China. One the other hand, it may get the Chinese some Latin American votes in the United Nations and the Latin American goodwill. China would have furnished only nuclear guarantees which appear meaningless at least in the present context of their nuclear development programme and the American proximity to Latin America. China would of course still be free to carry out subversion because it would have given no such guarantee in this regard.


The famous newspaper Neue Zeurcher Zeitung, has carried a report datelined Mexico, May 8, 1966 (copy attached) which says that there were indications that China may be prepared to guarantee the status of the zone if the Latin Americans supported its admission into the United Nations. Diesel asked the Romanians the question whether China would really be interested in joining the United Nations at this stage. The Romanians, who should perhaps know better than any other East European country, barring Albania, replied that their information was that China was very much interested in joining the world organization.


Fourth Session of the Preparatory Commission


The fourth session of the Preparatory Commission is to be convened in Mexico on August 30, 1966. Meanwhile, all Governments or member states have been asked to submit their comments by July 15 on the draft treaty prepared by the third session. The comments will then be circulated by the Secretariat among those States so that their delegations may come prepared for a discussion at the fourth session.


NOTE: Tello is a member of the Mexican delegation to the ENDC – He was an Asst. Sec. of the Mexico Conference


Diesel is a First Secretary in the German Permanent Mission in Geneva and deals with disarmament matters. He attended the Mexico Conference as an observer on behalf of his Government.



Neue Zeurcher Zeitung, No. 2057, Dated 9th May, 1966 (evening edition)


Mexico City, 8th May, UPI


Plan of a denuclearized zone in Latin America – Peking’s offer of horse trading


As was learnt in Mexico from informed circles on Sunday, Peking is said to be prepared to lend its support to the creation of a denuclearized zone in Latin America, provided as a quid pro quo the Latin American countries supported Peking’s admission into the United Nations. A commission appointed by 19 Latin American States is at present drawing up a draft treaty which would declare the Western Hemisphere south of the 30th parallel as a denuclearized zone. Diplomatic circles in Mexico consider the Chinese concession to be part of a diplomatic offensive by Peking to gain influence in Latin America. The Commission has already authorized a Committee to take up negotiations with the Chinese government regarding a denuclearized zone in Latin America.




As a result of the commission, a draft treaty has been prepared for the creation of a Nuclear Weapon Free Zone. Brazil and Mexico have rival approaches to denuclearization.


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File No. F.W.II/102(56)/66. Obtained by Ryan Musto.

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