President Vladimir Putin accused Washington on Monday of plotting to undermine December parliamentary elections seen widely as a demonstration of his power in Russia.

Europe joined the United States in voicing concern over a weekend police crackdown on protests by an opposition that says it has been banished from the airwaves and from the streets by an overbearing Kremlin. Authorities portray the small groupings as western-backed remnants of the chaotic 1990s.

Putin, who must step down as president early next year, said Russia needed a strong defence sector to to discourage others from poking their snotty noses in our affairs.

He said he saw Washington's hand in a decision by the Organization for Security and Cooperation in Europe's ODIHR monitoring arm to abandon plans to observe the December 2 poll.

We have information that, once again, this was done on the recommendation of the U.S. State Department, Putin said at a meeting with activists of his United Russia party.

Actions such as these cannot wreck the elections in Russia. Their aim is to deprive the elections of legitimacy, that is absolutely clear. But they are not going to achieve that, he said in his home city of St Petersburg.

Two weekend rallies by a coalition of anti-Putin groups were broken up by police using truncheons. Former chess champion Garry Kasparov, one of the coalition's leaders, was one of dozens of people arrested.

OPPOSITION PROTESTS

In Brussels, European Commission President Jose Manuel Barroso said policing of the opposition protests at the weekend in Moscow and St Petersburg had been heavy-handed.

The right to peaceful free speech and assembly are basic fundamental human rights and I very much regret that the authorities found it necessary to take such heavy-handed action, he said in a statement.

Earlier, French Foreign Minister Bernard Kouchner said he was surprised by the violence at the protests and said Russia's government should explain its actions.

Putin is running in the election as No. 1 on United Russia's slate of candidates. Opinion polls indicate the party will win at least 60 percent of the vote -- helped by Putin's personal popularity -- with rivals trailing far behind.

The 55-year-old Russian leader has said he will step down next year and hand over power to a successor in line with a constitutional ban on a head of state serving more than two consecutive terms as president.

Putin, seen by many as bringing stability after the upheaval of the immediate post-Soviet era under predecessor Boris Yeltsin, has said he will endorse one of his lieutenants as a successor; but he has refused to say which one.

Analysts believe Putin will use the endorsement he receives in the December 2 vote as a springboard to ensure he continues to play a key role in molding policy even after next year's presidential election.

Some observers with Kremlin links have speculated that Putin might step down early and run in the presidential vote, exploiting a legal loophole to get around the three-term ban.

Russia's upper house of parliament, the Federation Council, officially named March 2 next year as the date of the presidential vote, shifting into a decisive phase the guessing game over what will happen when Putin's term ends.

After the date has been published in the official gazette on Wednesday, would-be candidates will have 25 days to apply to run in the presidential election.

The ODIHR observation team pulled out of their mission to Russia citing obstruction by Russian authorities. A spokeswoman for the body said Putin's comment about U.S. influence on the decision was simply not true.

(Additional reporting by Guy Faulconbridge in Moscow and Brussels and Paris bureaux)

(Writing by Christian Lowe, editing by Ralph Boulton)