Belarus strongman Alexander Lukashenko is set to maintain his forces in power on Sunday as people cast their ballots in a parliamentary vote boycotted by most of the opposition.

Polling opened at 8:00 am (0500 GMT) in the country of 9.5 million people, state television said, and would continue until 8:00 pm, supplemented by Soviet-style state-organized fairs and music concerts throughout the capital.

The United States on Wednesday accused a Belarus state-owned firm of supplying munitions to the Syrian government, as it announced new sanctions focused on the Syrian conflict.

The U.S. Treasury named Belarus firm Belvneshpromservice and the Syrian military's Army Supply Service for sanctions under U.S. executive order 13382 that identifies targets as proliferators or supporters of proliferators of weapons of mass destruction.

Sweden's embassy in Minsk has received a threat against Swedish nationals in Belarus, following the recent expulsion of the Swedish ambassador and diplomats, the foreign ministry said Sunday.

"The Swedish embassy has received a threat aimed at Swedes in general in Belarus," the embassy wrote on its webpage.

Unable to perform freely in their authoritarian homeland, half a dozen bands from Belarus are rocking against the regime at a music festival in Poland near the border with their country.

"This is a unique festival, where bands can sing in Belarussian and not in Russian and shout out 'Long live free Belarus'," Hanna Piekarska, spokeswoman of the annual BASowiszcza festival, told Agence France Presse by telephone as the two-day event got under way Friday.

A military court handed stiff prison terms to 19 Ukrainians, three nationals from Belarus and two Russians accused of serving as mercenaries for ousted leader Moammar Gadhafi in Libya's conflict last year.

One of the Russians, judged to have been the coordinator, was condemned to life imprisonment while the others were sentenced to 10 years' hard labor.

European Union foreign ministers will consider slapping fresh sanctions this week against Syria, Iran and Belarus as the bloc ramps up its drive to stop human rights abuse.

EU officials said ministers who gather in Brussels from late Thursday were expected to add 18 Iranians "responsible for serious human rights violations" to a blacklist of 61 people already under an EU travel ban and asset freeze.

Belarus has executed both men convicted of a Minsk metro bombing that killed 15 people in the nation's worst attack since its post-Soviet independence, state television reported on Sunday.

The report came a day after the sister of one of the two men, Vladislav Kovalyov, who had pleaded not guilty to acting as an accomplice, had told AFP that authorities had informed her of her brother's execution by gunshot.

Russia on Friday took control of the Belarus gas pipeline network in an economic rescue deal that will help Minsk survive isolation by the West and increase the Kremlin's influence over its neighbor.

Russian gas giant Gazprom said it would pay $2.5 billion to take the 50 percent stake it does not own in Beltransgaz in a deal easing pressure on the depleted treasury of Belarus President Alexander Lukashenko.

The European Union on Monday slapped fresh sanctions on Belarus and Iran in protest at human rights violations, diplomats said.

The sanctions, agreed at talks between the EU's 27 foreign ministers, target 16 people allegedly involved in rights abuse in Belarus and 29 in Iran with an assets freeze and travel ban.

Belarus on Tuesday gave a cool reception to Russian Prime Minister Vladimir Putin's surprise announcement he favors a merger between the two countries into one state as in the days of the USSR.

The opposition raised the alarm over what it said were Russian dreams to essentially annex Belarus while sociologists said that support for re-unification with Russia was dwindling in the country year-by-year.