Russia will supply Serbia with fighter jets, tanks and combat vehicles, a move that potentially strengthens Moscow's influence in the Balkans.

The six MiG-29 fighter jets, 30 T-72 tanks and 30 combat vehicles come from Russia's weapons reserves. The jets will need immediate overhaul after delivery in March, which will cost between 180-230 million euros (between $188-240 million.)

Serbian Prime Minister Aleksandar Vucic, who secured the deal during his visit to Russia on Wednesday, says the Russian "donation" will "dramatically" boost his country's defense capability. Most of Serbia's neighbors are NATO members.

Vucic says Serbia will remain militarily neutral despite the new weaponry from Russia.

Although formally seeking European Union membership, Serbia has been sliding toward traditional ally Russia.