Serbia is heading for a showdown next month between a nationalist who leans towards Russia and a liberal favouring the West following the first round of a presidential election.

Nationalist Tomislav Nikolic took 39.6 percent of the vote on Sunday in a field of nine candidates, ahead of 35.5 percent for pro-Western President Boris Tadic.

Analysts said the 61 percent turnout - the highest since the fall of strongman Slobodan Milosevic in 2000 - showed how seriously people took the vote on Serbia's place in the world, and turnout could be even higher in the February 3 run-off.

Both candidates oppose independence for the breakaway province of Kosovo. But Nikolic is lukewarm towards EU membership and argues that Serbia can steer a middle course between the 27-member bloc and Russia.

Tadic said Serbs must return to the polls in force on February 3 "to show that Serbia is absolutely not giving up its European course, the path it started on in 2000".

He warns of dark days if Nikolic wins. His opponent denies accusations of isolationism.

"Serbia voted today for both Europe and Russia," he told state broadcaster RTS. "The road to Russia is at this moment more open, and I'll open the road to the European Union."

Serbia was never a close ally of Russia in the days of the Soviet Union, but Moscow's backing for its bid to block the independence bid by Kosovo has reinvigorated feelings of Slavic brotherhood against the West.

To win the second round, the candidates must also attract third party votes with promises of higher living standards and jobs, as well as promising to keep Kosovo, which is heading for independence with Western support.

Tadic strongly backs joining the EU, despite most EU members and Washington planning to recognise Kosovo - Serbia's historic heartland - as independent within months.

Many Serbs feel the country has paid enough for its role in the Yugoslav wars of the 1990s and most want EU membership. The question is whether their resentment is greater than the allure of EU-fostered economic development.

In the run-off, analysts think supporters of pro-Western candidate Cedomir Jovanovic will vote for Tadic while Nikolic would pick up roughly the same share of the vote from Milutin Mrkonjic, candidate of Milosevic's once-mighty Socialist Party.

Political analyst Milan Nikolic said the outcome might be in the hands of nationalist Prime Minister Vojislav Kostunica, the backer of third-placed candidate Velimir Ilic.

Kostunica is Tadic's partner in Serbia's fragile coalition government but favours a hard line against the EU over Kosovo and is keen on closer political and economic ties with Moscow.

"Kostunica is again in a position to decide the fate of the country," Milan Nikolic said.