Russia's likely next president, Dmitry Medvedev, has vowed to stick by Belgrade in its fight against Kosovo's Western-backed declaration of independence from Serbia.
Mr Medvedev, the Russian deputy prime minister and Vladimir Putin's pick as successor, spoke after talks with nationalist Serbian Prime Minister Vojislav Kostunica and pro-Western President Boris Tadic.
He the first leader to visit Serbia since a mass anti-Kosovo independence rally in Belgrade on Thursday turned violent.
Kosovo's parliament declared independence from Serbia on 17 February.
The move has chilled relations between the East and West, with Belgrade and Moscow staunchly opposed and the US and European powers supporting Kosovo's split.
Ahead of the visit, Russia accused the US of seeking to humiliate Serbia over Kosovo, which the Belgrade government and most Serbs consider their historic heartland.
The statement followed a comment by US Assistant Secretary of State Nicholas Burns that Russia was aggravating tensions over the Kosovo issue.
As well as being in agreement on Kosovo, economic relations are strong between Belgrade and Moscow, with Russian state gas giant Gazprom buying Serbia's main oil company NIS last month.
The two countries have also signed deals to build an underground gas reservoir and a pipeline through Serbia to pump Russian gas to western Europe.
