At the beginning of September, Branko boarded a direct flight from Belgrade to Moscow. After a few days in the Russian capital, Branko, with three other Serbian nationals, was driven to a military recruitment centre in Krasnogorsk, a city on the outskirts of Moscow, where the group signed a contract with the Russian military. “It all went very fast; in one day I became a soldier for Russia … Now I am waiting to be sent to Ukraine,” Branko said in a text exchange on Telegram, requesting anonymity so he could speak freely. Branko, not his real name, was part of Moscow’s latest drive to recruit Serbs to fight for the Russian army in Ukraine, as the Kremlin seeks to replenish its forces, depleted by 18 months of fighting. Based on accounts provided by two Serbian fighters who travelled to Russia, as well as a leaked list of recruited Serbs, the Guardian found that Russian officials appear to have made plans to recruit hundreds of Serbian nationals to bolster the army. Since the start of the war in Ukraine, Russia has introduced a series of laws to lure foreign citizens to join its ranks. Vladimir Putin, at a security meeting shortly after his troops invaded Ukraine, said the Kremlin should help people from overseas who planned to fight on Russia’s side. Since then, the Russian leader has signed an order lowering the minimum length of contract military service for foreigners from five years to one, and offered a fast-track recruitment drive to non-Russian combatants. Serbia, an EU accession candidate since 2012, has struggled to balance historically close ties with Russia against aspirations for integration with Europe, and tensions have been exacerbated by the war in Ukraine, with many Serbs sympathetic to Russia. Pro-Russian sentiments run especially high among Serbia’s ultra-nationalist groups, who have organised a number of pro-Moscow rallies since the start of the war in Ukraine. While the number of Serbs recruited so far does not appear to be significant enough to make a tangible difference on the battlefield, Moscow’s actions risk straining its relationship with Serbia, one of its few allies in the west. Leading the Serbian recruitment scheme, a plan that appeared to have been devised over the summer, was Davor Savičić, a Serb who has spent years fighting as part of Russia’s first incursion into Ukraine in 2014. Savičić has also been linked with the Wagner paramilitary group. The Fontanka news outlet reported that he had previously fought in Syria with Wagner. Two sources close to the paramilitary group confirmed Savičić’s previous involvement to the Guardian. In an interview on 21 August with the prominent pro-Kremlin TV host Vladimir Solovyov, Savičić spoke openly about how he had been put in charge of a unit of Serbian nationals in Ukraine. “We are now officially signing a contract with the Russian ministry of defence. Soldiers go through the Krasnogorsk military registration and enlistment office,” he said, describing details that matched Branko’s recruitment account. After additional training, the guys are sent to the Luhansk direction,” Savičić added, referring to the eastern Ukrainian region that is one of Putin’s key targets. Sitting next to Savičić during the interview was another Serb, Deyan Beric, who told Solovyov that the Serbian fighters had enlisted as part of Russia’s 106th airborne division. “When Vladimir Vladimirovich [Putin] allowed foreigners to come, I made a plan for how it would all work and turned to my general,” Beric said, pointing to Savičić. “The guys arrive, we meet them, then they immediately go to the military registration and enlistment office, and sign a contract. “Most of the foreign volunteers in the Russian army are from Serbia,” he added. Beric, a skinny man with long black hair, had previously given interviews to Russian state media in which he described how he fought as part of the pro-Russian self-proclaimed Donetsk People’s Republic in Ukraine from 2014. Russian officials appear to be closely coordinating the recruitment process. The Russian-language service of the BBC, which last week first reported on the Serbian recruitment scheme, said it had obtained a private recording of a meeting between Savičić and unnamed officials in Moscow, in which Savičić said he planned to recruit up to 1,000 Serbian nationals that would form its own battalion as part of the 106th airborne division. Russia’s defence ministry was not immediately available for comment. The exact number of Serbs that have signed a contract with the Russian military remains unclear. Orden Respubliki, an anti-war Russian whistleblower group, has shared with the Guardian a list containing 13 Serbs who have reportedly signed up with the Russian military since September. Two of the 13 men named on the list, including Branko, responded to requests for comment from the Guardian. “We are about 60-70 men so far,” said one of the Serbs on the list, who also travelled from Serbia to Moscow in September, adding that he signed with the “106th airborne division.” The man said that he had decided to join the Russian military for “ideological reasons”, and that the lucrative military payouts played a “secondary role”. The recruitment drive risks fomenting tensions between Moscow and Belgrade. Last January, Serbia’s president, Aleksandar Vučić, reacted angrily on national TV after a Russian news video claimed to show Serbian volunteers training to fight alongside Wagner troops in Ukraine. “Why do you, from Wagner, call anyone from Serbia when you know that it is against our rules?” the president said, referring to the law that forbids Serbs to take part in conflicts abroad. The Serbian defence minister, Miloš Vučević, also warned Serbs against joining Russian ranks. More than two dozen Serbian nationalists have since been prosecuted. Viktor Zaplatin, a Russian war veteran who recruited Serbian volunteers in the fighting alongside pro-Russian forces in Ukraine in 2014, said Serbian authorities had cracked down on fighters going to Russia. “The risks of criminal prosecution for those who have gone to Russia and returned to Serbia is very high,” Zaplatin said. “There have always been volunteers from Serbia in Russia. This means that there are volunteers there now, but the number and in what capacity they participate and serve is an organisational secret.”