As the world’s attention remains focused on the wars in Ukraine and, more recently, the Middle East, several countries in the Western Balkans are ramping up their military capacities. 

This build-up is not a sudden reaction but part of a decade-long trend that has recently accelerated. Croatia and Serbia have both announced significant defence spending increases, while Albania and Kosovo are expanding their armed forces and embarking on domestic defence production projects. Meanwhile, the security situation in Bosnia continues to deteriorate, raising alarms about regional stability.

The evolving security landscape has also seen the emergence of new military alliances beyond the traditional divide between Nato members and non-members. Serbia, which is not a Nato member, has forged a defence partnership with Nato member Hungary. Albania, Kosovo and Croatia have formed a separate alliance – a development that has sparked consternation in Belgrade.

Both Croatia and Serbia have also announced plans to restore mandatory military service. 

Serbia goes public with military ambitions

Serbian President Aleksandar Vučić publicly confirmed on June 20 that Belgrade is strengthening its military capabilities in response to the trilateral defence cooperation agreement signed by its neighbours. 

Speaking in a televised interview on pro-government channel Prva, Vučić said that Serbia “will not be the first to fire” but must prepare cautiously against what he described as an emerging military bloc threatening Serbian interests.

“We are not threatening anyone. Serbia is a peaceful country. But we must be ready,” Vučić said.

Vučić revealed that Serbia has acquired “some of the most sophisticated weapons”, including advanced drones sourced both domestically and from abroad. He hinted at a significant upgrade of Serbia’s defence system, much of which he said has been kept secret.

In a further display of Serbia’s growing military presence, Vučić announced plans for a large-scale military parade in Belgrade in mid-September. “The Serbian army will show what it has at the big parade,” he said, promising to unveil previously undisclosed weaponry and systems.

Serbia’s military expansion reflects a strategy of balancing its ambitions to join the European Union with its close ties to Russia and China. Unlike Croatia, which aligns its military acquisitions with Nato and EU commitments supporting Ukraine, Serbia has maintained neutrality in the Russia-Ukraine war, even under strong pressure to pick a side. 

In recent years, Serbia procured a diverse mix of equipment from various suppliers: French Mistral air defence systems and Airbus C-295 transport aircraft from the West, alongside Russian military hardware. China has contributed its FK-3 medium-range air defence missile system and CH-95 drones. In January, Serbia reportedly signed a $335mn defence contract with Israeli military technology firm Elbit Systems, including advanced rocket artillery and drone systems, 

In August 2024, Serbia signed a €2.7bn deal with France for 12 Rafale fighter jets – a strategic pivot from Russian-made aircraft. The acquisition is Serbia's largest military procurement since its separation from Montenegro in 2006. “Serbia’s choice of Rafale jets is a clear signal of our long-term alliance,” French President Emmanuel Macron said at the time. Serbia plans to finance €1.9bn of the total through bank loans, Finance Minister Siniša Mali announced in June. 

At home, Serbia is boosting its defence industry. In May 2025, Serbian company PR-DC partnered with US-based Raven Autonomous Technologies to produce the IKA-Bomber drone for international markets.

Serbia is a major arms producer in the region, ranked 36th globally in arms exports in 2020-24, according to the SIPRI Arms Transfers Database.

Croatia’s military modernisation

Croatia has intensified its military investments in response to a more volatile global security environment, recently signalling a strong commitment to increase Nato defence spending to 5% of GDP.

While the country, as of 2024, had below average defence spending as a share of GDP for Nato members, Prime Minister Andrej Plenkovic and Defence Minister Ivan Anušić have repeatedly voiced plans to hike military spending. 

Anušić recently confirmed Croatia reached Nato’s 2% target this year and plans to increase spending to 3% in the near term, agreeing with US President Donald Trump’s calls for greater Nato contributions.

Croatia aims to raise defence spending to 2.5% of GDP by 2027 and 3% by 2030. Annual defence spending is expected to reach €2.7bn by then, a fivefold increase since 2016.

Croatia recently took delivery of its 12th Rafale fighter jet, completing a €1bn project to upgrade its air force with Western technology in what the government described as the country's largest military investment since gaining independence in 1991. 

Further modernisations include purchases of Bayraktar drones and eight new US-made Black Hawk helicopters. An interdepartmental commission led by Plenković will coordinate strategic defence investments and consider the use of EU budget flexibility clauses for increased defence funding.

This continues a process started a decade ago, that was ramped up after Russia’s 2022 invasion of Ukraine.

Defence industry revival

Albania is seeking to revive its domestic weapons industry amid growing geopolitical instability in Europe and the Middle East. Albania ceased domestic arms production after the collapse of its communist regime, but recent geopolitical developments have prompted a policy shift.

Having ceased arms production after the fall of its communist regime, Albania is now reauthorising state-owned company KAYO to form a joint venture with a private partner to produce specialised military vehicles. The private partner must produce Nato-standard armoured vehicles, including for export. 

Additionally, Czech defence firms are eyeing cooperation with Albania, focusing on ammunition and propellant production, airspace and traffic control systems, and introducing AI-based surveillance and cybersecurity tools.

Albania’s commitment to revitalising its arms sector is supported by EU aid, and it continues to provide military assistance to Ukraine.

In Kosovo, Prime Minister Albin Kurti also announced plans to set up a domestic arms industry amid heightened tensions with neighbouring Serbia. The establishment of a domestic military production capability is seen as a strategic response to the evolving security landscape in the region.

"Since 2021, we have doubled the number of soldiers, tripled the Ministry’s defence budget, quadrupled overseas training opportunities for our officers, non-commissioned officers and soldiers, and significantly increased investments in armaments and ammunition," Kurti said when outlining the plans in November 2024. 

Pristina has selected Turkish defence firm Makine ve Kimia Endustrisi (MKE) to build the country’s first ammunition factory, a major step toward establishing a domestic arms industry. The factory will produce 5.56mm and 7.62mm ammunition and eventually develop drones.

Kosovo is also deepening defence cooperation with the US through a new framework agreement covering defence planning, strategic capabilities, and Nato integration. Minister of Defence Ejup Maqedonci has confirmed that Kosovo will receive US-made Javelin missiles this year and is exploring defence initiatives beyond Nato’s KFOR mandate. 

In May, Kosovo hosted Nato’s largest military exercise on its soil, Defender Europe 2025, with 25,000 troops participating.

North Macedonia already exceeds Nato’s average defence spending and plans further increases. Foreign Minister Timčo Mucunski affirmed in May the country’s commitment to meeting and maintaining the Nato 2% spending threshold, demonstrating readiness to confront future challenges.

Prime Minister Hristijan Mickoski added that with ongoing military modernisation projects, defence expenditures will continue to rise.

New military alliances

A feature of the Western Balkans’ evolving security dynamics is the formation of new military partnerships.

On March 18, Kosovo, Albania and Croatia signed a trilateral military declaration in Tirana to enhance defence cooperation, interoperability and joint exercises. The pact supports Euro-Atlantic integration, particularly Kosovo’s aspirations for regional defence collaboration.

Anušić, Maqedonci and Albanian Defence Minister Pirro Vengu stressed the alliance’s focus on regional stability and countering hybrid threats, stating it was not directed against any third party.

Serbia condemned the pact as provocative and destabilising. Vučić accused Croatia and Albania of fuelling an arms race and demanded explanations for Belgrade’s exclusion from consultations. 

Just weeks later, Serbia and Hungary signed a strategic defence partnership amid rising regional tensions. Vučić framed the deal as a response to the trilateral defence pact between Albania, Croatia and Kosovo. 

The agreement, signed by defence ministers Bratislav Gasic and Kristóf Szalay-Bobrovniczky, encompasses 79 joint military activities up to the end of 2025, including helicopter exercises and aims to deepen bilateral defence cooperation.

The partnership extends beyond defence to energy, with Serbia approving an oil pipeline to Hungary, reducing dependence on Russian routes. Hungary has supported Serbia’s EU accession and opposed Western sanctions on Serbian energy assets linked to Russia.

Vučić praised Hungary’s support, citing shared “sovereignist” policies and resistance to EU pressure over Moscow ties.

Regional hotspots 

There have been concerns since Russia’s invasion of Ukraine that Moscow is seeking to provoke tensions in the Balkans to divert Western attention from the war in Ukraine.

The EU enhanced its policing presence in Bosnia & Herzegovina immediately after Russia’s invasion of Ukraine, concerned about destabilisation risks in the Western Balkans.

The invasion took place months after the parliament in Bosnia’s Serb entity, Republika Srpska, voted in 2021 to withdraw from the Bosnian army and other state institutions, raising fears this was a step towards the breakup of Bosnia.

Since then, Republika Srpska’s secession minded president Milorad Dodik has continued efforts to reject the authority of both Bosnia’s state institutions and the international community’s high representative. Most recently, Republika Srpska’s government passed a bill to establish a reserve police force, ostensibly for emergency situations but widely seen as formalising paramilitary groups.

Northern Kosovo, predominantly Serb-populated, remains another flashpoint. Serbia and Kosovo came close to an agreement on normalisation of their relations in early 2023, but since then relations have deteriorated and there have been several violent incidents in the volatile region. 

The situation was further complicated by the new war between Iran and Israel.

In Kosovo, there are fears that Serbia may exploit the current international focus on the Middle East to pursue its own geopolitical interests in northern Kosovo, according to several experts surveyed by Ekonomia Online. 

“If the US and its allies shift focus entirely to the Middle East, Kosovo could be left exposed to threats from Serbia,” Criminology professor Fatmir Çollaku told the outlet. “Kosovo lacks advanced defensive systems like missiles, leaving it vulnerable,” he warned. Security analyst Drizan Shala echoed these concerns, suggesting, “Belgrade could seek to exploit geopolitical shifts for its own gain.” 

With the world’s attention trained on flashpoints elsewhere, the steady militarisation of the Western Balkans is unfolding largely out of the spotlight – but not without consequence. The combination of arms build-ups, competing alliances and long-standing territorial disputes is a concerning mix in a region still haunted by memories of past wars. Indeed, Trump recently claimed to have prevented a war in the region – without going into specifics – and pledged in a social media post to “fix” the situation.