Serbia's Deputy Prime Minister Aleksandar Vulin described his country as an "ally of Russia" on Wednesday, as he met Putin on the sidelines of an economic forum in Vladivostok on Wednesday.

"Maintaining or even increasing the ties with Russia during the time of its illegal aggression against the Ukrainian people, is not compatible with EU values and is not compatible with the EU accession process," EU foreign affairs spokesperson Peter Stano said.

Serbia was granted EU candidate status in 2012 and has been in the waiting room for membership since.

As part of the accession process, countries commit to align their foreign policy with that of the EU, Stano said.

"So, we expect Serbia to refrain from intensifying links and contacts with Russia," he told a press conference in Brussels.

The Balkan country has historically close ties with Moscow and is almost entirely dependent on Russian gas.

It condemned Russia's war in Ukraine at the United Nations but has refused to sanction the Kremlin.

Serbia "will never become a NATO member, will never impose sanctions on the Russian Federation, and will never allow any anti-Russian actions to be carried out from its territory", Vulin said in comments carried by Russian television.