The ruling party of Vladimir Putin Monday won Russia's parliamentary elections but with a sharply reduced majority, in a blow for the Russian strongman ahead of his planned return to the Kremlin in 2012.

United Russia is set to obtain 238 seats in the 450-seat State Duma, down sharply from the 315 seats it won in the last polls in 2007, election commission chief Vladimir Churov told reporters citing results from 96 percent of polling stations.

Russians voted Sunday in elections set to see Vladimir Putin's ruling party win a reduced majority in parliament, amid claims the authorities were engaging in foul play to ensure it maintained dominance.

Russia's main independent vote monitors have been denounced and harassed by the authorities ahead of the polls while several opposition news websites were the victims of an apparent mass hacking attack on polling day.

Russians in the Far East began voting Sunday in key parliamentary elections expected to hand victory to Vladimir Putin's party amid claims of campaign fraud and unprecedented intimidation of observers.

"Polling stations are open," Konstantin Mikhailov, head of the local election commission in the city of Anadyr in the resource-rich Chukotka region, told Agence France Presse.

Russians prepared Saturday for parliamentary elections amid dwindling support for the ruling United Russia party and unprecedented pressure on election observers.

Voting in the world's largest country will begin at 2000 GMT Saturday in the Russian Far East regions and end 21 hours later when polling stations close at 1700 GMT Sunday in the exclave of Kaliningrad wedged between Poland and Lithuania.

Russian strongman Vladimir Putin on Sunday agreed to be the ruling party candidate in 2012 presidential elections that he is certain to win and that will fix the country's political future.

His nomination at a glitzy congress of United Russia was a formality after President Dmitry Medvedev announced in September he would give way for Putin in the March 2012 polls and instead take the job of prime minister.

A top Russian opposition group accused Vladimir Putin's ruling party on Saturday of preparing to win next week's parliamentary polls through fraud and threatened mass protests in case of an unfair result.

A Moscow rally organized by A Just Russia -- the smallest of four parties in the State Duma lower house of parliament -- drew some 500 protesters to a small square near the Kremlin under threatening skies.

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 upper house of Russia's parliament on Friday formally set March 4, 2012 as the date for the presidential election, a vote expected to see Vladimir Putin return to the top job.

"The elections for the president of Russia are set for March 4, 2012," the Federation Council said in a statement on its website after senators approved the date in a vote called for under the constitution.

Russian Prime Minister Vladimir Putin Friday called for restraint over the Syria crisis, after talks with his French counterpart who accused President Bashar Assad of being deaf to pressure.

"We are calling for restraint and caution. This is our position," Putin told a news conference, the day after his foreign minister had likened the situation in Syria to a civil war.

Vladimir Putin, known for his earthy sense of humor, made a rare appearance on a popular Russian comedy show, seeming to relish a vulgar gag about Stalin and wincing at a Lada joke.

Putin seemed to cry with laughter at some points and at other times looked deeply uncomfortable, as he sat in the front row at the show, aired as a recording on state television late Sunday.