Introduction

When the Soviet Union disintegrated in 1991, the three newly independent states of Belarus, Kazakhstan, and Ukraine inherited a considerable number of nuclear weapons in their territory2. Ukraine effectively became the third largest nuclear-armed state, with some 5,000 Soviet nuclear warheads stationed on its territory as well as a large number of intercontinental ballistic missiles (ICBMs)3. Despite Kyiv’s initial commitment to become a non-nuclear weapons state (NNWS), it proceeded along a difficult path toward the accession of the Treaty on the Non-Proliferation of Nuclear Weapons (hereafter the NPT) (^{Budjeryn, 2015}, 2022).

On December 5, 1994, with the signature of the ‘Memorandum on Security Assurances in Connection with Ukraine’s Accession to the NPT’ in Budapest (Hungary) between Ukraine and three NPT depositary states (United States, Russia, and the United Kingdom), the debate on Kyiv’s claim to own these weapons faded4. The document uttered that the Ukrainians accepted to renounce nuclear weapons with the security assurance5, given by the United Nations Security Council (UNSC) permanent members6, that its sovereignty and territorial integrity were res- pected ^{(United Nations, 1994, p. 2)}. Ukraine’s part of the pledge was fulfilled in July 1996, when the last nuclear warhead left Ukraine’s territory to Russia for dismantlement. This pledge was concluded in 1996 when Ukraine settled the return of all Soviet-era nuclear warheads to Russia for its complete elimination as part of the Nunn-Lugar Cooperative Threat Reduction (CTR) program7 (^{Hecker, 2016}a).

However, first, due to the annexation of Crimea and the subsequent war in eastern Ukraine in 2014, some countries, mainly the United States (hereafter the U.S.) and other North Atlantic Treaty Organization (NATO) members, argued that Moscow’s disrespect for the sovereignty and territorial integrity of Ukraine is a direct violation of the so-called Budapest Memorandum of 1994 (e.g., ^{Budjeryn, 2018}; ^{Kühn, 2018}b, ^{Yost, 2015}). Second, on February 24, 2022, Moscow’s full-fledged invasion of Ukraine marked a critical challenge to European security and deepened Russia’s breach of the Budapest Memorandum (^{Vicente, 2022}a, 2022b). Hence, despite a renewed public and academic discussion regarding Ukraine’s nuclear status, the country remains until today committed to the NPT regime as an NNWS.

About the European Union’s (EU)8 international involvement in Ukraine’s nuclear status, it can be characterized from an elusive and marginal common policy in the sphere of disarmament, between 1991 and 1996, to an ‘unassuming’ and precarious common and coherent non-prolife- ration policy, after Russia invades Ukraine. In both timeframes, the EU had relied on the U.S. to take the lead. Thus, since there was not a clear Common Foreign and Security Policy (CFSP) in the field of nuclear disarmament in the past (when Ukraine possessed nuclear weapons), and despite today’s particularly strong emphasis on the non-proliferation policy element (rather than on disarmament), Brussels failed to seek Russia’s assurance that it would refrain from any threat or use of force against the territorial integrity or sovereignty of Ukraine under the Budapest Memorandum on security assurances, in connection with Ukraine’s accession to the NPT as an NNWS.

In the context of this article, my objective is to describe what was and is the role of the EU, even if inexistent or seeming unassertive, on Ukraine’s nuclear status. The EU’s involvement (even if marginal) can be analyzed into two distinct and historical moments. First, I propose to study the role of the EU during the period between the dissolution of the Soviet Union and the complete dismantlement of nuclear weapons in Ukraine. Second, I examine the EU efforts to promote non-proliferation and nuclear disarmament agenda between the two critical junctures of 2014 Russia’s covert invasion of eastern Ukraine and 2022 Moscow’s full-fledged invasion of Ukraine territory, but I also scrutinize the effects of these two major events to the current Euro- pean security and nuclear order.

1. EU responses to the dismantlement of soviet/Russian nuclear weapons in Ukraine (1991- 1996)

Since Ukraine’s independence in 1991, there was an unstable socio-economic situation, and the legal framework that would regulate issues related to safety and security was also absent. Un- der such conditions, illegal acts involving nuclear or radioactive materials in the Ukrainian terri- tory increased significantly (^{Kuzmyak and Kravtsov, 2012}). As a result, the EU showed its interest primarily in the physical protection of nuclear facilities and materials of the former Soviet states, which would lead to the establishment of the European Community’s Technical Assistance for the Commonwealth of Independent States (TACIS). Brussels was more concerned in that period about the energy aspects of nuclear safety, mostly generated by the fears of the 1986 Chornobyl disaster9. Yet, hither and thither, the EU tackled the issue of nuclear disarmament in Ukraine through Common Statements.

First, under its fragile European Political Co-operation (EPC)10 framework, the EU and its member states, in the statement on the “‘recognition of former Soviet republics” of 31 December 1991, expressed their readiness to proceed with recognition based on the assurances received and on the understanding that all republics, including Ukraine, “on whose territory nuclear weapons are stationed”, will adhere shortly to the NPT as NNWS ^{(European Parliament, 1992a)}.

This pledge was followed by guarantees of technical support in dismantling these weapons in Ukraine. Thus, in the context of various Common Statements11, at the EPC Ministerial Meeting in Lisbon, on 17 February 1992, the EU agreed “to convey to the authorities of the countries of the former Soviet Union their readiness to render any appropriate technical support they may need to eliminate nuclear weapons and to establish an effective non-proliferation system” ^{(European Parliament, 1993)}. This objective was allured one month before in Strasbourg, when former Foreign Portuguese Minister João Deus Pinheiro, at the time representing the Presidency of the European Union, during a parliamentary debate, assured that eliminating the stockpile of nuclear armaments in the former Soviet Union states was:

a matter of concern not just to the countries of the European Community, but to virtually the entire international community, including the states that have emerged from the break-up of the Soviet Union itself. The declarations and undertakings that have so far been made by the au- thorities of the various states are, in my opinion, encouraging. They represent a step in the right direction, but a variety of technical and practical measures also need to be implemented. For this reason, we welcome the fact that the... U.S. is granting nearly USD 400 million to finance the dismantling of strategic nuclear weapons. We believe that similar steps will have to be taken about tactical nuclear weapons. Furthermore, it might be necessary to send experts on both the civilian and the military uses of nuclear power to the former Soviet Union, shortly, to work to gether with the various local authorities to ensure nuclear safety ^{(European Parliament, 1992b)}.

Moreover, under point 17.3 of the joint conclusions of the second institutionalized ministe- rial meeting between then the European Community and the Rio Group12 in Santiago de Chile, held on 28 and 29 May 1992, Brussels promoted and reinforced the EU’s commitment toward di- sarmament, by urging Ukraine and the other two former-Soviet states (Belarus and Kazakhstan):

…to accede to the non-proliferation regime as… NNWS . Rio Group and EU Member States …welcomed the completion of the transfer to Russia of short-range nuclear we- apons, as announced recently, before their dismantlement. The Ministers also welcomed the signature in Lisbon on 23 May by the United States, Russia, Belarus, Kazakhstan, and Ukraine to an agreement on the implementation of START13 (Council, 1992).

In this sense, there was a notion at that time, in which the EU officials presumed that Ukraine was prepared to accept the treaties and abide by existing arms reduction agreements, such as the NPT and Strategic Arms Reduction Treaty (START). However, the situation on the ground was quite different.

In one way, Mariana ^{Budjeryn (2014}, 2018, 2022), a leading scholar on Ukraine’s nuclear disarmament, contended that one of the most controversial issues with the NPT was Kyiv’s claim to ownership of its nuclear inheritance as a successor state of the Soviet Union. This claim, “more than any other issue, complicated the process of its nuclear disarmament,” argued ^{Budjeryn (2015, p. 212)}.

From another standpoint, Nikolai ^{Sokov (2013}, p. 89), a former Russian diplomat and a prominent scholar on nuclear non-proliferation, defended that during the period of uncertainty, from January 1990 to May 1992, Moscow also encountered in Ukraine a situation of loss of control over its nuclear weapons, which was translated into the “risk that elements of the state mechanism with ultimate right and responsibility to use nuclear weapons (for example, the head of state) might lose these prerogatives”. These prerogatives included the breakdown and the pene- tration of the command-and-control systems. Ultimately the reality was that: Ukrainians did not have operational control nor the ability to use these weapons (or political motivation).

The academic debate about this issue has been critical to interpreting Ukraine’s de facto ope- rational control over its inherited nuclear weapons. As Robert Norris (2014), Senior Fellow for Nuclear Policy at the Federation of American Scientists, sustained:

Ukraine was never a nuclear power. Ukraine did have several thousand soviet/Russian wa- rheads deployed within its borders, but the button command and control was always in Moscow. The weapons systems were guarded and manned by Russians. Ukraine had no operational control over them or any way to launch or fire them. Had the Ukrainians tried to seize the missiles, bombers or warheads, there would have been a bloody confrontation with the Russian military.

Nikolai ^{Sokov (2013}, pp. 90-91) added that “officers in control of some strategic delivery vehicles in Ukraine took the oath of allegiance to Ukraine, which gave the government of that country a capability to use these assets, although reportedly not the capability to arm weapons’’. Furthermore, Polina Sinovets (personal communication, July 19, 2022), head of the Odesa Cen- ter for Nonproliferation, argues that historical documents sustain that “Ukraine military had not the command and control over tactical soviet-nuclear weapons in Ukraine but if they wanted, they could as there were no blocking mechanisms on tactical nuclear weapons in the Soviet Union”.

In this context, unlike ^{John Mearsheimer’s (1993)} case for a Ukrainian nuclear deterrent, nonproliferation scholars such as Maria Rost Rublee (2015), Associate Professor of International Relations at Monash University, deconstructed the notion that Ukraine would retain some kind of deterrent power if it would manage to keep its former Soviet nuclear weapons. Her argu- ment relied on technical inadequacies, political-military risks, and strategic unreliability of those Soviet nuclear weapons inherited by Ukraine. In addition, ^{Steve Miller (1993)}, Director of the International Security Program at Harvard Kennedy School’s Belfer Center, in his case against a Ukrainian nuclear deterrent explained that even if those weapons had a deterrent effect by no means would prevent entirely the spectrum of armed conflict or nuclear war.

Second, with the entering into force of the 1992 Maastricht Treaty, the EU gained full CFSP competencies. Thus, under the CFSP, the EU did two things until the end of 1996. On the one hand, following the submission of the START I/Lisbon package to the Ukrainian Parliament (Verkhovna Rada) in November 1992, the EU’s foreign policy in the field of nuclear disarmament was essentially coherent in paying ‘lip service’ to the U.S. diplomacy in supporting the disman- tlement of nuclear weapons in Ukraine. Brussels had a common voice but did not have a voice of its own.

On the other hand, the EU continued to support TACIS programs and its nuclear safety agenda, which was invaluable and complementary to the US-Russia dismantlement policy (es- sentially under the auspices of the Presidential Nuclear Initiatives of George H. W. Bush and the congressional Nunn-Lugar CTR program) in the former Soviet states, including Ukraine. By 1996, Kyiv completed the elimination of its nuclear weapons and transferred all other Soviet-era strategic warheads to Russia14.

2. EU efforts to promote non-proliferation and nuclear disarmament goals in Ukraine (2014-Present)

Since the 2014 annexation of Crimea and the subsequent war in Ukraine, military tensions between NATO and Russia are steaming. The Russian covert operation is a direct violation of the 1994 Budapest Memorandum in which Moscow, along with the U.S. and the United Kingdom, agreed to respect the independence, sovereignty, and territorial integrity of Ukraine. As men- tioned, a key element in securing Kyiv’s agreement to transfer all Soviet-era nuclear warheads to Russia for elimination (^{Yost, 2015}). In addition, Moscow’s nuclear weapons policies play an important role in the renewed confrontation15 (^{Kühn, 2018}a, p. 738). This situation places an uncomfortable focus on the value of the security assurances pledged to Ukraine by the nuclear powers in exchange for its denuclearization (Sinovets and ^{Budjeryn, 2018}).

Moreover, “Russia’s actions have also damaged the further integrity of these so-called nega- tive security guarantees, which nuclear weapon states (NWS) provide to NNWS in exchange for the latter respecting their non-nuclear obligations under the NPT” and has also contributed to weakening the global nuclear non-proliferation and disarmament regime (^{Kühn, 2018}a, p. 738). As a result, the continuing tug-of-war between US/NATO and Russia over Ukraine heightened the deterioration of the Euro-Atlantic security environment and the advent of a new nuclear arms race.

As far as Europe is concerned, the crisis in Ukraine “has given way to Russian nuclear saber rattling through not just rhetoric but also the deployment of short-range nuclear-capable mis- siles to the Russian exclave of Kaliningrad”, which borders two EU member states: Poland and Lithuania (Rapnouil et al., 2018, p. 2). A setting that poses considerable security imbalances to the post-Cold War stability in Europe.

In response, with the approval of the European Council on 20 March 2014, Brussels strongly condemned at first the illegal annexation of Crimea and Sevastopol by the Russian Federation (European Council, 2014). Since then, the EU has adopted a strict non-recognition policy re- garding illegal annexation. This policy led to substantive sanctions against Russia and the EU’s association agreement (final) negotiations with Ukraine. Regarding the latter, and in the context of Russia’s violation of the 1994 Budapest Memorandum, the EU is politically engaged in making sure that Kyiv would not obtain nuclear weapons or other weapons of mass destruction (WMD). Thus, when the Association Agreement between the EU (including EURATOM and its Mem- ber States), and Ukraine was signed on 29 March 2014, which entered into force on 1 September 2017, the parties agreed under Article 11 of the Agreement to include the following WMD or non-proliferation clause:

The Parties consider that the proliferation of… WMD , related materials, and their means of deli- very, to both state and non-state actors, represents one of the most serious threats to international stability and security. The Parties, therefore, agree to cooperate and to contribute to countering the proliferation of weapons of mass destruction including nuclear weapons , related materials and their means of delivery through full compliance with, and national implementation of, their existing obligations under international disarmament and non-proliferation treaties and agreements and other relevant international obligations. The Parties agree that this provision constitutes an essential element of this Agreement.

In 2020, despite the EEAS Special Envoy for Disarmament and Non-proliferation holding continuous non-proliferation and disarmament dialogue meetings with Kyiv, neither the last Annual Progress Report on the implementation of the EU WMD Strategy nor the most recent Association Implementation Report on Ukraine does not have references to any nuclear weapons activities in Ukraine (Council, 2022b; ^{European Commission and HR/VP, 2022)}. It is unclear if the absence of references is due to the non-existence of activities or to the lack of implementation of the agreement’s conditionality obligations.

It is clear, however, that threat perceptions by EU member states, especially the ones with historical ties and geographical proximity to Moscow, have increased after Russia’s military ag- gression against Ukraine, which had an impact on the decision-making (national security) policy of those countries and therefore on EU’s foreign policy as well (^{Vicente, 2022}c). It is evidenced by the coincidence between the rise in European defense budgets and Russia’s war on Ukraine (Rapnouil et al., 2018; Bruno and Cozzolino, 2022).

Russia’s threat to use nuclear weapons in the context of its war on Ukraine has been a stark reminder that this threat is real (^{Immenkamp, 2022}). In the first ten weeks of the military cam- paign, Moscow issued around 20 nuclear signals (^{Arndt and Horovitz, 2022}). Nuclear weapons were central to Russia’s war on Ukraine from the outset. As a result, we can note that Moscow’s full-fledged invasion of Ukraine inflicted a major wound on the current nuclear order (e.g., Vi- cente, 2022a; Mecklin, 2022, ^{Bollfrass and Herzog, 2022}). First, it weakened the NPT regime. Se- cond, it increased the likelihood of the use of nuclear weapons (e.g., ^{Giovannini, 2022}; ^{Talmadge, 2022}; Cirincione, 2022).

As far as the EU is concerned, despite Russia’s war on Ukraine, Brussels remains a non-

-proliferation actor (not a nuclear deterrent one) that supports the NPT as the cornerstone of the global nuclear disarmament and non-proliferation regime (^{Vicente, 2018}, 2022b).

As an NPT regime guarantor, the EU supports the idea that nuclear proliferation is poten- tially the greatest threat to international and European security, requiring a concerted and multi- lateral response (Council, 2003, 2022a). For example, confronted with new proliferation challen- ges emerging from Russia’s invasion of Ukraine and its direct impact on the stability and security of Europe, the 2022 EU’s Strategic Compass reiterated the EU commitment to preserving the disarmament, non-proliferation, and arms control architecture by supporting the centrality of the NPT and all obligations under it “in a way that promotes international stability, peace, and security” (Council, 2022a).

Conclusion

All things considered, while Moscow’s invasion of Crimea and Donbas back in 2014 was a first opportunity for Europeans to confront Russia along with the resultant violation of the 1994 Budapest Memorandum pledged to Kyiv in exchange for denuclearization, the EU post-2014 po- licy in the field of nuclear disarmament and non-proliferation towards Ukraine was ambivalent. Initially, there was an EU unstructured and non-coherent (common) position due to its member states’ diverse threat perceptions regarding Russia.

However, 24 February 2022 marked a critical and deeply disturbing challenge to the current NPT regime and European security architecture with the Russian invasion of Ukraine (^{Vicente, 2022}a). More than a shift in Europe’s security environment, which is already reshaping the nucle- ar order, the war in Ukraine is also a turning point in Brussels’ approach toward Moscow (^{Loss, 2022}; ^{Vicente, 2022b}).

Presently, it appears to be a once-in-a-lifetime unity and coherence among Europeans in support of economic sanctions against Moscow, a renewed appetite for military and defence, advocacy for an exceptional humanitarian and refugee policy (at least within the EU), as well as unprecedented solidarity toward the Ukrainian people. As a result, there is a common position on the EU’s foreign policy to uphold the NPT’s nuclear security risks posed by Russia-Ukraine quarrels around Zaporizhzhia Nuclear Power Station, but the EU responses in the field of nuclear disarmament and non-proliferation toward Ukraine remain somewhat ambivalent. A foreign policy that, however, lacks resources or means to supervise the advent of a potential pursuit of nuclear weapons on behalf of Ukraine.