PODGORICA: Montenegro's ruling party faced a tough test in national elections on Sunday, hoping its promise to bring the country into NATO and closer to the European Union will outweigh opposition allegations of corruption.

Prime Minister Milo Djukanovic, 54, has presented the vote as a choice between continuing Western integration under his Democratic Party of Socialists or being reduced to a "Russian colony" under the opposition.

But the opposition say his regular accusations that they are funded by Moscow are false and a smokescreen to cover for the culture of cronyism and organised crime that they say he has allowed to flourish over his quarter-century of dominance.

NATO invited the tiny Balkan country of 620,000 to join last year, partly out of concern at Russian influence in Montenegro, which has strong cultural and commercial links to its traditional Orthodox Christian ally.

Supporters of the move say it will bring greater security and prosperity. But it remains divisive - NATO bombed Montenegro when the alliance intervened in 1999 to end a campaign of ethnic cleansing in Kosovo by Serbia, with which Montenegro was then in a state union.

A lack of reliable polls makes the election hard to call, but long-term allies have deserted Djukanovic, suggesting that the message from opposition parties may have traction.

Voter Vojislav Grujovic, a stocky manual labourer in his 50s, declined to say who he had chosen on Sunday. "I have voted without worries, because everyone pledged a better life and prosperity ... We can't lose," he joked.

The former Yugoslav republic's economy has grown at a brisk 3.2 percent a year for the past decade, thanks mainly to foreign investment, much of it from Russia as well as China and Italy, targeting energy, mining and tourism in a country famed for its spectacular mountains and sea coast.

At an opposition rally in the capital Podgorica on Saturday, hundreds of backers of the Democratic Front (DF), an alliance of pro-Serb and pro-Western parties, waved Serb, Russian and Montenegrin flags, chanting their campaign slogan "Us or Him".

"Djukanovic, step down peacefully on Sunday if you love Montenegro?," said Nebojsa Medojevic, a pro-Western politician and one of the DF's leaders.

Polling stations close at 1800 GMT, with first partial results expected an hour later.