BEIRUT (Reuters) - About 10,000 Lebanese students, chanting "America out", marched to the U.S. embassy near Beirut on Tuesday to protest against Washington's policy in Lebanon.

The protest, called by pro-Syrian parties including Shiite Muslim Hizbollah, came three days after clashes between police and a much smaller anti-U.S. demonstration in downtown Beirut.

But there was no sign of trouble as protesters, waving Lebanese flags, defied winter weather to march to the U.S. embassy complex in Awkar village north of the capital.

Hundreds of police blocked roads leading to the embassy and stopped the crowds from reaching the complex itself. "America stay away from Lebanon so that the civil war does not return," the crowd chanted.

"Beirut is free, America out."

The protest coincided with a worsening political crisis that has paralysed the government and split it between pro-and anti-Syrian factions.

The crisis escalated in recent days with a row between Hizbollah and anti-Syrian Druze leader Walid Jumblatt that revived memories of the 1975-1990 Lebanese civil war.

Jumblatt accused Hizbollah -- a close ally of Syria and Iran -- of hiding behind its "weapons of treachery", capping a month-old campaign against the group that is under pressure to disarm in line with a UN resolution.

The standoff spilled over into a public slanging match after a flurry of diplomatic efforts failed last week to reach a compromise over a U.N. inquiry that has implicated Syria in the murder of former Prime Minister Rafik al-Hariri in February.

The U.S. embassy in Beirut issued a statement denying a front-page report in the local as-Safir newspaper that quoted Ambassador Jeffrey Feltman urging the government to sack Shiite ministers, who include two from Hizbollah.

"By inventing such a story, as-Safir clearly hopes to provoke increased tensions in Lebanon," the embassy said.

"In addition, because of the dangers that some people will mistakenly believe such stories and act upon then, the embassy must consider these fabrications to be a direct threat against Ambassador Feltman's safety," it said.

The protesters carried a large picture of Feltman written under it: "Recipe for war".

"We reject guardianship. Everything that happens in Lebanon now happens under American guardianship after we had Syrian guardianship," Ahmad Taleb, 22, said.

The United States supports a coalition of anti-Syrian groups in parliament and government and urges the disarming of Hizbollah in line with a 2004 UN Security Council resolution.

Washington has threatened Security Council action against Syria if Damascus did not cooperate fully with the U.N. inquiry.

International pressure and Lebanese protests forced Syria to end its 29-year military presence in Lebanon in April.

The Financial Times reported that Saudi Arabia has presented Lebanon and Syria with a plan to defuse tensions between Syria and Lebanon.

Saudi Foreign Minister Prince Saud al-Faisal told the FT in an interview that the kingdom had made proposals for an agreement, but was waiting for a response from Beirut and Damascus, and details would have to be worked out.