Balkans Breakthrough for Ukraine: Bring Serbia into NATO & the Kosovo Model into the Donbas

With his stunning¹ reversals² on Ukraine³, President Trump seems ready to give up his bid to halt Russia’s war on its smaller, beleaguered neighbor.  He shouldn’t.  Even with stepped-up US support for Kyiv, including expanded intelligence⁴, authority⁵, and ability⁶ to strike deeper into Russia, the grinding war and “savage strikes”⁷ from Moscow will continue. Trump can move the parties towards his original, correct goal of a ceasefire by turning to the Balkans – a nearby theatre of competition in which the US and its allies hold strategic leverage. With his trademark audacity, the US President can exploit Putin’s obsessions with Serbia and Kosovo, defining a path for a territorial settlement with Ukraine while summoning additional pressure on the Kremlin to accept it.

Instead of the amorphous, ineffective call for war-ending “land swaps”⁸, the White House can propose that Kyiv and Moscow accept an interim arrangement on the Donbas and other contested territory modeled on UN Security Council resolution 1244⁹ – the Russian-backed terms for Kosovo following the NATO intervention a quarter century ago. Crucially for Ukraine, this resolution sidestepped the question of Kosovo’s sovereignty – envisioning a final settlement based ultimately on “the will of the people.”¹⁰ Establishing a purely “provisional … transitional” UN administration, resolution 1244 opened a trajectory for Kosovo to eventually secede from Serbia, without declaring or denying Pristina’s independence from Belgrade. Zelensky is far more likely to accept such an arrangement, which allows the Ukrainian President to tell his citizens that Donbas is still part of Ukraine and that the people of Donetsk and Luhansk (and agreed neighboring oblasts) will ultimately decide which country has dominion over them.

Benefitting Kyiv, demographics in the Donbas and other contested territories are far more mixed than in lopsided Kosovo, where any referendum on independence was a foregone conclusion. Aided by the US, Ukraine and Russia can negotiate modalities for displaced persons and refugees to vote in the final settlement referenda. As required under the Ukrainian¹¹ Constitution¹², final approval would rest on a referendum among all Ukrainian voters. As in Kosovo, overall administration of the Donbas would pass to the United Nations, or possibly the Organization for Security and Cooperation in Europe (OSCE). Kyiv would see a halt to the intensive Russification of annexed Donbas, including the seizure of property, imposition of Russian passports, and military indoctrination of children. As in the Balkans, the UN or OSCE would set up property commissions, enabling displaced persons to assert their claims free from Russian barriers, fostering refugee return.

Crucially for Russia, the 1244 model would instantly sever Kyiv’s exercise of even symbolic sovereignty over the Donbas and environs, including in agreed areas that Russia does not control – and has little chance of controlling. In 1244, the Security Council implicitly mandated that there was ‘no going back’ – no reversion of Kosovo to Serbian control. Indeed, in November 2005, Russia, the US, and the three other members of the Contact Group set ”Guiding Principles”¹³ stipulating¹⁴ that “… Kosovo does not return to the pre-March 1999 situation.”

Russia, Ukraine, and the US could apply this model today, agreeing upfront on a broad “no return to the pre-war situation” principle, while expressly contemplating partition, union of Donbas with Russia, or a new form of integration within Ukraine, as the people of that region decide. Going beyond constructive ambiguity, the parties would set out defined, potential end-states that encompass Moscow’s position on sovereignty. Ratified at the Security Council, this represents a powerful inducement for the legalistic Putin. With a political template for the Donbas in hand, the vital discussion on security guarantees – the false promise of the Putin-Trump Alaska Summit¹⁵ – can begin. Like 1244, the US-brokered Security Council resolution will incorporate detailed security provisions, including on peacekeeping forces. Putin can hardly complain about employing the 1244 model. The Russian leader has religiously demanded “strict adherence”¹⁶ to Security Council resolution 1244 on Kosovo, while repeatedly invoking the “Kosovo precedent”¹⁷ as justification to annex Ukrainian territory. Speaking before the Duma in March 2014, Putin declared that the situation in Crimea “is absolutely the same¹⁸…as Kosovo’s secession from Serbia.”

In the wake of his February 2022 invasion, an emphatic Putin told UN Secretary-General Antonio Guterres that the recognition of Kosovo as an independent state was the “precedent”¹⁹ for Russia to recognize independent Donbas. Putin is also on record conferring respect for the will of the people. Proposing annexation to the Duma in March 2014, Putin declared that Crimea had held “a referendum … in full compliance with democratic procedures and international norms.” In September 2022, Putin proclaimed that “referendums have been held … the ballots have been counted and … the people [of Donbas and neighboring regions] have made their unequivocal choice²⁰ [to secede.]”

Right now, it doesn’t matter that the referenda were shams, that Putin’s words are cynical devices — or that the Russian leader’s aim remains turning Ukraine into a puppet-state. What matters is urgently reviving US-led diplomacy by forcing Russia and Ukraine to respond to constructive American proposals for a ceasefire. Putin’s devotion to 1244 and his endorsement of referenda create an opening. As Ukraine’s battlefield prospects improve with increased US support, so will the prospects for diplomacy – grounded in the practical, face-saving UN model for Kosovo that the Russian President has championed for over two decades. Putin’s bitter grievance²¹ over Kosovo²² also opens the door for a breakthrough with Serbia – one that can finally pull Belgrade from the Kremlin’s orbit and boost US leverage over Moscow. More than Slavic brotherhood, history, or anti-American antipathy, the Russo-Serbian relationship rests on staunch opposition by the Kremlin to Kosovo’s independence. Alongside China, Russia uses its Security Council veto to keep Kosovo out of the UN, in support of Belgrade’s hostility towards its former province. Isolating Kosovo remains Serbian President Aleksandar Vučić’s top foreign policy priority, underpinning Belgrade’s close relations with an array of malign actors, including Iran²³ and Venezuela²⁴, as well as Russia²⁵ and China²⁶.

In a rare, open rebuke, Serbian media in April 2022 accused²⁷ Putin of a “stab in the back” after the Russian President told Secretary-General Gutteres that “the Kosovo precedent” allowed a seceding state to bypass the “central authorities”²⁸, implying either Kyiv or Belgrade. “[Putin] has taken … the deciding step in recognizing Kosovo²⁹…making it easier for Washington and the West to resolve it,” observed Srećko Djurić, former Serbian Ambassador to Belarus. Unlike President Biden, who missed the golden opportunity³⁰ to sever Belgrade’s strategic partnership with Moscow at that time, President Trump can induce the decisive rupture by offering Serbia and Kosovo membership in NATO. Washington’s offer and Belgrade’s acceptance will have an immediate, transformative effect in and beyond the Balkans. Shattering its self-imposed taboo³¹ on joining the Alliance, the embrace of NATO by Serbia – Russia’s oldest, tightest friend in Europe – will deliver a swift, unsettling blow to Putin and a geopolitical setback for both Moscow and Beijing.

Unlike Belgrade’s dilatory EU membership charade³², the breathtaking commitment to join NATO – ending Serbian neutrality – is incompatible with Vučić’s multi-vectored foreign policy or his revival of Greater Serbian nationalism. For Belgrade, accepting membership in NATO – which bombed Serbia in the 1999 air campaign³³ over Kosovo – means finally accepting the results of the aggressive wars launched under President Slobodan Milošević. With the largest, most destabilizing country in the Balkans finally in the Western camp, Trump can take credit for bringing the entire 35-year drama over Yugoslavia to a close. No longer will the unstable Balkans serve as a playground for Russian hybrid warfare, Chinese economic subversion, or languish as a ‘grey zone’ for organized crime, drug trafficking, and other security threats.

A dramatic about-face for Trump and an irreversible step when consummated, renewed expansion of the Alliance will resonate strongly with Kyiv, making its territorial concessions more feasible. The Administration’s³⁴ security³⁵ ‘assurances’³⁶ will become more assuring to Ukraine, with the unequivocal US commitment to NATO demonstrated in the Balkans. Zelensky will take succor knowing that vital Serbian ammunition³⁷ will flow directly to Ukraine, unimperiled by threats from Moscow. The offer of membership to Kosovo and Serbia will underscore Alliance agency, demonstrating that NATO makes strategic decisions, whether about the Balkans or the Eastern Flank, free from external pressure.

Facing the worst crisis³⁸ of his twelve-year rule, Vučić has good reason to accept the offer. Trump’s astronomical³⁹ popularity in Serbia – his highest⁴⁰ in the world – makes the US President the one figure who can make NATO membership palatable in the country. The long-postponed decision⁴¹ by the Trump Administration to enforce Biden-imposed sanctions⁴² on Serbia’s national oil company, NIS (Naftna Industrije Serbia), opens a striking new phase in Serbia’s relations with Russia and the US. Belgrade will suddenly have to decide whether its continuing dalliance with Moscow – which has so far refused to withdraw Gazprom Neft from its ownership position in NIS – is worth the serious economic and political hit that Serbia will see. Among the options that Vučić must consider is forcibly exiting Gazprom Neft by nationalizing NIS. Such a dramatic breach with the Kremlin would set the stage for the decisive step to join NATO.

The long-postponed decision⁴³ by the Trump Administration to enforce Biden-imposed sanctions⁴⁴ on Serbia’s national oil company, NIS (Naftna Industrije Serbia), opens a striking new phase in Serbia’s relations with Russia and the US. Belgrade will suddenly have to decide whether its continuing dalliance with Moscow – which has so far refused to withdraw Gazprom Neft from its ownership position in NIS – is worth the serious economic and political hit that Serbia will see. Among the options that Vučić must consider is forcibly exiting Gazprom Neft by nationalizing NIS. Such a dramatic breach with the Kremlin would set the stage for the decisive step to join NATO.

Belying negative government narratives, Belgrade has cordial relations⁴⁵ with⁴⁶ NATO⁴⁷, both in Serbia and Kosovo, where the KFOR peacekeeping force retains popularity. Coincidentally, the new Serbian Ambassador to Washington, Dragan Šutanovac, has vigorously advocated that Serbia “accept reality” and advance its economic and security interests by joining NATO. Trump will sweeten the offer with a hefty investment and defense package under the US-Serbia Strategic Dialogue launched by the Biden Administration⁴⁸. The decision to join NATO will inject a new dynamic into the unyielding national protests⁴⁹, chiefly over government corruption and lack of accountability, issues that have long since eclipsed Kosovo. While hardline nationalists will assail Vučić over NATO, his base – as obedient as Trump’s – will swallow their leader’s decision, actively promoted by compliant national media. The prospect of serious reform required by NATO, along with revived EU accession, will attract significant parts of the opposition. Suddenly, the early elections and electoral reforms that Vučić has resisted will no longer appear so daunting.

With his flair for spectacle, Trump will invite the leaders of Serbia and Kosovo to the Oval Office – as he did in his first term⁵⁰ – to sign membership commitments (conditioned on NATO-required reforms and accession process) and the seminal peace agreement that has eluded all of Trump’s predecessors going back to President Clinton. The Historic President Trump Agreement between Kosovo and Serbia will also formally codify the dormant EU Normalization Agreement⁵¹ between Kosovo and Serbia, along with its Annex⁵². The offer of NATO membership alone – the alpha and omega for Kosovar Albanians – will convince any Kosovo Prime Minister, including the hardline caretaker Premier, Albin Kurti, to finally establish a measure of self-rule for Kosovo Serbs. Given a pathway to join NATO, Kurti or any Kosovo Prime Minister can satisfy Belgrade’s long-standing demand⁵³ and sign the EU draft statute⁵⁴ creating the “Association of Serb Majority Municipalities.”

Vučić will recoup the ‘Association’ without needing to formally recognize Kosovo, beyond the de facto recognition already attributed⁵⁵ to Belgrade and Pristina. For all his government’s bluster, Vučić understands that the Serbian position on Kosovo has never been weaker. A series of audacious moves by Kurti in the Serb-dominated north have marginalized legacy Serbian institutions and undermined Belgrade’s hopes for partition.

There are good reasons for the mercurial⁵⁶ Trump, who once scorned tiny Montenegro’s⁵⁷ accession to NATO, to change course on Kosovo and Serbia. Unlike in Ukraine, the burden and risks of expanding the Alliance in the Balkans – separated from the Russian landmass by a gauntlet of NATO countries – are virtually nil. NATO retains absolute supremacy across the region. Only three countries in the Balkans are not Alliance members: Bosnia-Herzegovina, Kosovo, and Serbia, the only one to rule out membership. In every other country, NATO accession has boosted stability, reduced net costs to the U.S, and increased American influence and investment prospects.

NATO expansion to Kosovo and Serbia would further reduce America’s security burden. NATO forces, including US troops, are already saddled with protecting Kosovo. Trump himself has repeatedly⁵⁸ underscored the volatility of the situation, claiming at the UN⁵⁹ General Assembly, at the NATO Summit⁶⁰, and in the Oval Office that he stopped Serbia from “a big time war on Kosovo.” A Serbia-Kosovo agreement grounded in NATO membership will instantly calm tensions, allowing NATO and US troops to reduce their presence right away, and eventually to leave altogether. Republican members of Congress grasp the logic of NATO expansion in the Balkans. Brian Mast, the conservative Chair of the House Foreign Affairs Committee, has introduced legislation⁶¹ directing the State Department to “support … Kosovo’s …membership in NATO” and, “to encourage … Serbia to reduce or cease strategic engagement with the Russian Federation and … China”.

As Kosovo and Serbia prepare to become Allies in as soon as three years, formal recognition will become far less contentious. Like Greece and Turkey, Greece and North Macedonia, and Croatia and Montenegro, the transformative and tangible prospect of joining NATO – along with a reduction in tensions and an increase in trade – will assuage even Pristina and Belgrade. With the help of the adroit NATO Secretary-General Mark Rutte and his able Deputy, Radmila Šekerinska, former Macedonian Defense Minister, Washington can persuade the North Atlantic Council⁶² to offer the pathway to NATO for Kosovo and Serbia. Trump’s diplomatic breakthrough with the feuding Balkan parties, along with some legal sophistry, will win over even the four NATO Allies⁶³ that do not recognize Kosovo. Long-awaited Greek⁶⁴ recognition of Kosovo will likely follow the White House signing ceremony of the Trump agreement, boosting pragmatism in Romania, Slovakia, and Spain – none of which needs to immediately recognize Pristina.

By going outside the box in the Balkans, the Administration can achieve an outsized impact in Ukraine.  Drawing on Putin’s convictions on Serbia and Kosovo, Trump can win valuable leverage over Moscow, viable concessions from Kyiv, and the serious consideration of the Nobel Committee.