BELGRADE, Serbia — Russia on Thursday accused Serbia of exporting arms to Ukraine, saying it’s a stab in the back by its longtime Slavic Balkan ally.

“Serbian defense enterprises, contrary to the ‘neutrality’ declared by official Belgrade, continue to supply ammunition to Kyiv,” the Russian Foreign Intelligence Service, SVR, said in a statement.

The statement alleged that the export of the Serbian arms to Ukraine are going through NATO intermediaries, “primarily the Czech Republic, Poland and Bulgaria. Recently, exotic options involving African states have also been used for this purpose.”

Serbia’s populist President Aleksandar Vucic told the state RTS television that he has recently discussed the issue of the arm exports to Ukraine with Russian President Vladimir Putin and that it was agreed that the two countries form a “working group” to establish how Serbian-made weapons reach the Ukrainian frontlines.

Serbian arms exports to Ukraine, mostly the Soviet-era-caliber ammunition still used by Ukraine’s defense forces, have long been known since 2023, but it’s not clear why the Russian foreign security service decided to react now.

In March, Serbia denied it exported arms to Ukraine after Moscow demanded to know if it had delivered thousands of rockets for Ukraine’s fight against Russia’s invasion.

The SVR statement said the arms sales are being carried out through a “simple scheme using fake end-user certificates and intermediary countries” serving as “a cover for anti-Russian actions.”