Yugoslavia had a strong track record as a vocal supporter and occasionally even an influential promoter of nuclear non-proliferation and disarmament. These policies were deeply embedded in the broader global anti-colonial struggle in which Yugoslavia, as one of the founders of the Non-Aligned Movement, took an early lead in the international political arena. Carefully crafted policies and statements about non-proliferation gave this mid-sized European nation much greater political leverage than it would otherwise have had. More importantly, Yugoslavia went beyond political propaganda and followed them to the letter. 

Having developed or acquired a complete nuclear fuel cycle technology, including the fuel reprocessing and plutonium extraction by the mid-1960s, albeit most of it on the experimental scale, the country’s official plans indicated its exclusive use for independent development of the nuclear energy sector, based on open cooperation with other countries and the IAEA. Putting these words and promises into action, Yugoslavia signed the NPT soon after it was opened for signature in 1968 and ratified it in the National Assembly in 1970, thus granting the country an even stronger position to promote global nuclear disarmament amidst the emerging détente between two Cold War superpowers. 

A much darker and cold-blooded calculation lay in the backdrop of such a rosy narrative. Recent scholarship reveals that the Yugoslav political establishment's only concern was the country’s security and that corresponding nuclear policies were tailored exclusively to achieve that goal.[1] The tangible threat of invasion by the Soviet Union after the Tito-Stalin split of 1948 raised the interests of Josip Broz Tito and his closest associates in providing maximum support to the country’s budding nuclear program, changing its original course to the production of an atomic bomb in the shortest period of time. When the Soviet threat began to dissipate following the outbreak of the Korean War and Stalin’s death in 1953, Yugoslavia’s main challenge became halting or slowing down nuclear proliferation in Europe, particularly in West Germany and Italy. Yugoslav officials estimated that West German or Italian acquisition of the bomb would trigger a domino effect and cover the continent with nuclear warheads, thus erasing the country’s hard-won independence. The nightmare of being surrounded by nuclear-armed countries of two opposing blocs with no or only a limited nuclear arsenal was as tangible as the previous threat of Soviet invasion. The only solution to this puzzle for Yugoslavia was to voice its concerns in international forums to support any initiative for nuclear non-proliferation and the existing political and military status quo, while also secretly developing the country’s nuclear capabilities as fast as possible to meet future challenges better prepared. 

The same logic continued during and after the 1968 Soviet invasion of Czechoslovakia. Fearful of being the next in line for Soviet intervention, the Yugoslavs managed to secure informal security guarantees from the United States, which gave them enough breathing space to ratify the already signed NPT as soon as possible.[2] Once again, it was estimated that the Treaty would solidify the existing state of affairs and save the country from a long-term engagement in a nuclear arms race that would overstretch its economy and unavoidably fail to deliver an adequate result, even in the best-case scenario. Another benefit was the promise of support for developing nuclear technology for peaceful purposes. 

Having finally ticked all the main boxes of the national security policy through the NPT, the secret nuclear-weapon project and most of the nuclear technology development became superfluous and were practically abandoned by 1971. 

Fast forward to 1974, when the Indian ‘peaceful nuclear explosion’ and the consequent establishment of the Nuclear Suppliers Group (NSG) left Yugoslav nuclear policy in tatters. The NPT, as the crowning achievement of decades-long Yugoslav diplomatic efforts and the only guarantee for maintaining the global nuclear equilibrium, was considered a dead letter. The mere establishment of the Nuclear Suppliers Group (NSG), particularly its rapidly expanding “trigger list,” further shattered the country’s security calculations, simultaneously undermining ambitious and somewhat naive expectations of becoming an equal partner in the global nuclear technology trade. 

Abandoning the position of a nuclear non-proliferation and disarmament promoter was not an option for Yugoslavia. Neither was the acceptance of the changed circumstances in the nuclear technology trade. The solution was found in a covert breach of the NPT. Yugoslavia’s security policies reverted back to a previous mode, and the country resumed a secret nuclear weapons program at a time when the NPT seemed powerless to stop further nuclear proliferation. The disillusionment with what the Yugoslavs perceived as a failed promise of ‘non-discriminatory’ sharing of peaceful nuclear technology among the NPT signatories led to the decision to start an illicit nuclear technology trade with other aspiring nuclear and ‘rogue’ nations, such as Pakistan, Iraq, and North Korea, and to a certain extent even the People’s Republic of China. 

While these exchanges produced limited gains for all parties involved, the Yugoslav experience offers a critical warning for contemporary decision-makers: even a small and relatively underdeveloped country can build up its nuclear potential in a relatively short period of time, successfully hide it behind the official non-proliferation policies actively promoted in the global political community, and engage in nuclear technology trade that can fly beneath the radar of dedicated observers for years, causing disproportionate damage to global nuclear security. An equally important lesson is that to fully understand the effects of any change in the existing NPT regime, a comprehensive analysis of security policies, internal dynamics, and motives behind them must be performed on any nation that has developed or is close to developing its nuclear capacities. 

Associated Documents

Document No. 1

Poverljivi izveštaj DSIP-a o sastanku kod druga Đure Ničića [Classified Report of the DSIP on a Meeting with Comrade Đura Ničić], April 2, 1962, f. 11, 177, AJ (Arhiv Jugoslavije – Archive of Yugoslavia).
Throughout the 1950s, Yugoslav nuclear policy was designed by President Tito and a small circle of his closest associates. Very few official documents from that time remain or indeed ever existed. Things began to change after the establishment of the UN Eighteen Nations Disarmament Committee (ENDC) in December 1961, followed by the committee’s first meeting in March 1962, which marked the beginning of global negotiations that eventually led to the signing of the Partial Test Ban Treaty (PTBT) in 1963. This initiative forced the Yugoslav political leadership to approach the problem more systematically. 

The short document presented here comes from the first meeting during which the Yugoslav nuclear policy started to be officially formulated. The meeting was organized by the Yugoslav State Secretariat for Foreign Affairs [Državni sekretarijat za inostrane poslove — DSIP] and included representatives of the Yugoslav People’s Army [Jugoslovenska narodna armija — JNA], the Institute for International Politics [Institut za međunarodnu politiku] and the Federal Nuclear Energy Commission [Savezna komisija za nuklearnu energiju — SKNE]. The main goal was to initiate the coordination of activities and permanent consultations between these institutions in order to provide expert support to the DSIP and better comprehension of the ongoing negotiations in the ENDC.

Document No. 2

National Archives of India (NAI), Transfer List 224, Ministry of External Affairs, Historical Division (R&I Section), 1950-1972 [Research and Intelligence Section] 6(59)- R&I/58 – Reports (other than Annual) from Yugoslavia. Monthly Report of the Indian Embassy in Belgrade, for the Month of March 1958, April 8, 1958

The following document provides a peculiar insight into the Yugoslav security calculations and non-proliferation thinking in the late 1950s, which did not change much in the following decades. The excerpt from the report of the Indian ambassador in Belgrade, Rajeshwar Dayal, reveals some of the ideas the Yugoslav Ministry of Foreign Affairs shared with one of the country’s closest allies to explain its diplomatic initiatives in the field. It also reveals how much importance Yugoslavia attached to the potential nuclear-weapon proliferation in Europe and its consequences, with a particular focus on West Germany and Italy and how their nuclearization would affect the country’s security. 

Interestingly, the document shows that Yugoslavia was desperately trying to hide its secret nuclear-weapon project from India, suggesting that, if necessary, it could acquire nuclear weapons from the Soviet Union, which was never even a remote possibility. The last comment also throws a different light on the diplomatic dynamics between Yugoslavia and India, as the suggested involuntary close cooperation between Yugoslavia and the Soviet Union was most likely designed as a clever move to motion India to provide full support for this Yugoslav initiative in global forums. Finally, Yugoslav support for the Rapacki Plan can be better explained from the perspective of Tito’s security calculations, rather than as a simple change of the country’s political course toward the Soviet Union. However, it is a fact that Tito never ceased to be a communist and that he was interested in finding a way to receive an honest blessing for his independence from Moscow. 

“[…] Meanwhile, the flow of nuclear missiles to Germany, to Italy and therefore to the East European countries will place Yugoslavia in a position of a permanent military inferiority when today she can boast of having one of the strongest standing armies in Europe, outside Russia. Were she to attempt to rectify the balance by asking for similar weapons – and these can only come from the Soviet Union – that would mean the end of her distinctive position in Europe. Yugoslav policy is, therefore, today directed with a single mindedness of purpose towards fending off this danger which threatens. The Yugoslavs are pressing hard in support of the Rapacki Plan for atomic disengagement and they are working for its extension to cover Hungary as well as the Balkan countries and Italy. At the same time, they are anxiously looking around for support for their inclusion in the Summit talks, where they can hope to influence the fateful decisions that will determine the future pattern of relationships in Eastern and Central Europe.” 

“[…] Reactions to the missile arming of West Germany

The decision of Adenauer’s Government on the strength of its parliamentary majority, and in the teeth of nationwide opposition to equip the Bundeswehr with nuclear weapons, came as a painful shock to the Yugoslavs. It has revived a good deal of the emotional bitterness against the Germans engendered by the events of the last war. The military resurgence of Germany, of which they along with many other European countries stand in dread is again beginning to cloud the horizon. Foreign Minister Popovic [Konstantin ‘Koča’ Popović] has repeatedly told me that the arming of West Germany with nuclear missiles is regarded with the utmost gravity, not only because of the inherent danger which such a step entails, but also because it throws considerable doubt on the sincerity of the United States in the search for a solution to the disarmament question. There is accordingly a mood of bitter frustration which the explanation of the Western countries, namely that the step is intended to provide a bargaining counter at the conference table, has done little or nothing to alleviate. 

Yugoslavia has announced her intention of raising the issue in the United Nations as representing a threat to international Agreements. It is emphasized that Yugoslavia has a justified anxiety since she was twice the victim of German aggression, and more so as a Peace Treaty has not yet been concluded with Germany. The record of Germany in spite of solemn pledges in the past two decades, is a standing warning against accepting Adenauer’s present pious declarations. Secondly, the danger of arming a power with which there is no Peace Treaty cannot be overlooked. Thirdly, Germany itself is still divided and the nuclear arming of one part of Germany cannot fail to have repercussions on the other part and will make the problem of reunification well nigh impossible. Fourthly, in some ways Germany is a nerve centre of all the tension between East and West and to introduce atomic armaments into that delicate area is certainly likely to enhance the danger of a general explosion.”

Document No. 3

Pitanje ratifikacije ugovora o neširenju nuklearnog oružja. Uprava za međunarodne organizacije (UMO). Grupa za razoružanje, međunarodnu bezbednost i miroljubivo korišćenje nuklearne energije [The Question of Ratification of the NPT. Office for International Organizations (UMO). Group for Disarmament, International Security and Peaceful Use of Nuclear Energy], May 12, 1969, f. 222 UN, 1968, PA, DA MSPRS (Diplomatski arhiv Ministarstva spoljnih poslova Republike Srbije – Diplomatic Archive of the Ministry of Foreign Affairs of the Republic of Serbia).

This rather long document is part of the materials prepared by the Yugoslav State Secretariat for Foreign Affairs [Državni sekretarijat za inostrane poslove — DSIP] for the deliberations regarding ratification of the NPT.  The excerpt presented here provides a clear insight into the final stage of the Yugoslav strategic thinking and development of nuclear policies that gradually evolved since the mid-1950s. These were the main motivations for the eventual ratification of the Treaty in 1970. 

“[…] Considering the abovementioned goals of the Treaty, and its application, the following concrete benefits for Yugoslavia would be achieved:

Our security in relation to FR Germany and Italy is increasing [original emphasis]. Namely, if there were no Treaty and if nuclear weapons proliferation would occur in Europe, FR Germany and Italy would be the first to acquire them. If we, in a particular set of circumstances, were forced to go for military nuclearization, it would be a lot slower and less efficient, considering our much weaker financial and technological capabilities. Therefore, our security is, in our opinion, greatest if none of our potential enemies has nuclear weapons. Consequently, it is in the interest of Yugoslavia to directly advocate for the absolute prevention of further nuclear weapons proliferation. Since our concept of nuclear weapons non-proliferation is more comprehensive than one in the Treaty, Yugoslavia should constantly insist on that wider concept that would aspire for the withdrawal of nuclear weapons from foreign territories, oceans and seas, suspension of training foreign armies in handling with nuclear weapons and in general, stopping of the so-called ‘vertical’ proliferation of nuclear weapons, that is, its further sophistication and multiplication by the existing nuclear powers. 

It gives us [Yugoslavia] the possibility to advance the development of modern technology in the nuclear field much faster than it would have been the case without the Treaty. The Treaty demands that nuclear powers assist non-nuclear [nations] in the peaceful use of nuclear energy and that, by doing so, ‘declassify’ many secrets in nuclear technology. If we use it properly, this advantage usually means great savings in basic research because others’ already acquired results, inventions and technology would be used.

Considering this possibility, which fulfillment would predominantly depend on how these activities and procedures would be organized internationally, it is very important for Yugoslavia to engage itself directly so these international routes and instruments would be more suitable for us. This is an ongoing process, and because of that, it is important for Yugoslavia to be engaged in it. 

However, for our engagement on the international level to be as concrete and advantageous as possible, it has to be based on clearly designed and elaborate long-term and short-term plans for our development in the peaceful use of nuclear energy. 

It gives us a better position for direct engagement in the efforts to achieve certain measures of disarmament and security. As the signatory of the Treaty on Non-Proliferation, Yugoslavia could advocate in international forums for disarmament and security more than if it were not a signatory of the Treaty because the Treaty in its spirit and concrete articles (preamble, article IV) provides these possibilities. Considering that Yugoslavia, based on its political concepts, believes that military alliances and blocs are not the forms through which security should be pursued, aiming instead for disarmament and further evolution of forms of collective security through the UN, it is logical that she fights for the fulfillment of such possibilities, for which the Treaty provides better conditions than if it were out of it.”

Document Nos. 4-5

Jugoslovensko-indijski odnosi, 27. april 1972 — 24. jul 1974. Strogo poverljiva Informacija o značaju i posledicama indijske nuklearne eksplozije (preliminarna) [Yugoslav-Indian Relations, April 27, 1972 — July 24, 1974. Top Secret Preliminary Information on Significance and Consequences of the Indian Nuclear Explosion], May 24, 1974, I-5-b/39-10, 837 KPR, AJ; Inženjersko korišćenje nuklearnih eksplozija [The Engineering Use of Nuclear Explosions], July 24, 1974, I-5-b/39-10, 837 KPR, AJ (Arhiv Jugoslavije – Archive of Yugoslavia).

These two documents come from the personal archive of Yugoslav President Tito and constitute a part of the set prepared for him by the State Secretariat for Foreign Affairs [Državni sekretarijat za inostrane poslove — DSIP] and scientists from the Boris Kidrič Institute of Nuclear Sciences [Institut za nuklearne nauke Boris Kidrič – IBK] in Vinča (near Belgrade, Serbia), the central nuclear institute in the country. The characteristic signature at the top of the first page confirms that Tito had read them. They are important in understanding how Yugoslav support for the NPT started disappearing soon after the Indian PNE in 1974. They also provide insight into how the entire process of nuclear (or any other) policy formulation functioned in Yugoslavia and how much control over the events Tito had. 

Document No. 6

Stenografske i magnetofonske beleške sednica SIV-a i radnih tela. Stenografske beleške sa sednica Komisije za nuklearnu energiju, 1979. Stenografske beleške sa sednice Potkomisije za tekuća pitanja Komisije SIV za nuklearnu energiju [Stenographic and tape-recorded notes of SIV (Savezno izvršno veće – SIV; Federal Government) sessions and working bodies. Stenographic Notes of the Sessions of the Nuclear Energy Commission, 1979. Stenographic Notes of the Session of the Current Affairs Subcommittee of the SIV Nuclear Energy Commission], April 16, 1979, f. 4229, 130, AJ (Arhiv Jugoslavije – Archive of Yugoslavia).

This excerpt is a part of the lengthy document from the Yugoslav Nuclear Energy Commission meeting held on April 16, 1979. The discussion included cooperation with different countries in the development of peaceful nuclear technology, exploration of options to acquire and sell uranium (yellowcake) on the global market without any restrictions, and joint programs in developing or exporting nuclear technology (Romania, Indonesia, and Iraq). 

The focus here is on investigating the possibility of constructing a nuclear reactor in Iraq in cooperation with France. The details are fuzzy, although it is undoubtedly the Osiraq nuclear reactor. Important for understanding the context is the fact that Yugoslavia and Iraq had already established lucrative barter arrangements on the principle “armaments for oil.” More importantly, the general undertone throughout this and other meetings of the Commission in a previous couple of years is the attempt of the Yugoslavs to find loopholes in the existing safeguards and other restrictions related to selling sensitive nuclear technology to other countries based on a belief that the NPT did not function and that the ‘nuclear haves’ were once again trying to reestablish much stricter monopoly on nuclear technology than before. 

[1] Marko Miljković, ‘Tito’s Proliferation Puzzle: The Yugoslav Nuclear Program, 1948-1970’ (PhD Thesis, Central European University: Department of History, Budapest and Vienna, 2021).

[2] Miljković, ‘Tito’s Proliferation Puzzle’, 488-489. Much like in the late 1940s, after the Yugoslav breakup with the Soviet Union, informal security guarantees were the perfect solution for Yugoslavia. The US Ambassador Elbrick personally assured the Yugoslav President Tito that occupation of Yugoslavia by the Soviets would not be acceptable, as it would directly jeopardize the NATO South Wing (Italy, Greece and Turkey). From the Yugoslav perspective, such guarantees were also a good enough solution, as they did not compromise the country’s non-alignment policy, while providing enough amount of deterrence directed towards the Soviet Union.