Hundreds of thousands of Hezbollah-led protesters rallied today at the doorstep of Prime Minister Fouad Siniora in an attempt to force the resignation of his government.
Hezbollah, Lebanon's most powerful Shi'ite Muslim group, and its pro-Syrian allies had called on Lebanese from across the country to take part in the protest in the capital Beirut, to be followed by an indefinite sit-in near the government offices.
The protesters regard the government a US puppet. "I call on the prime minister and his ministers to quit," Christian opposition leader Michel Aoun said to the cheers of protesters in downtown Beirut.
Speaking on behalf of the opposition, Mr Aoun demanded a national unity government.
A senior opposition source said supporters who had imposed a blockade on the government offices from where Mr Siniora and most of his ministers were monitoring the protest, later eased it and opened a road to the complex after contacts between opposition leaders and Arab diplomats.
Several thousand opposition supporters set up tents near the offices and planned to spend the night there. Large numbers of security forces, backed by armoured troop carriers, were deployed.
Scores of soldiers, using barbed wire and metal barriers, cordoned off the complex.
Mr Siniora and many ministers were inside as crowds massed, waving red-and-white Lebanese flags. Sources close to the organisers estimated the crowd at more than 1 million.
Hezbollah deputy chief Sheikh Naim Kassem had said before the protests the campaign would continue until Mr Siniora's cabinet fell.
"This government will not take Lebanon to the abyss. We have several steps if this government does not respond but I tell them you will not be able to rule Lebanon with an American administration," he told Hezbollah's al-Manar television.
Hezbollah has been in dispute with the Siniora's government over what it says was its failure to back the group during the July-August conflict with Israel.
Mr Siniora said yesterday his government would not quit. The anti-Syrian politicians who control the cabinet say the Shi'ite Muslim group and its allies want to stage a coup.
The government was weakened last month by the resignation of six opposition ministers and the assassination of anti-Syrian Christian cabinet minister Pierre Gemayel.
His funeral drew tens of thousands into central Beirut, with many mourners accusing Damascus of being behind the killing.
Druze leader Walid Jumblatt, the most prominent anti-Syrian leader, urged supporters to remain calm and avoid street confrontations. He said Hezbollah wanted to install Syrian and Iranian tutelage over the country.
"We will remain steadfast," he told a news conference today. "We will remain in our houses and fly the Lebanese flags ... We will wait for a month, for two months ... and watch them."