BEIRUT, Lebanon - The Lebanese opposition, led by the pro-Syrian militant group Hezbollah, called for mass protests to back demands for a change of the Western-backed cabinet of Prime Minister Fuad Siniora.

"The opposition forces, on the basis of their constitutional rights, call on all Lebanese, whatever their religious confession, to demonstrate peacefully in an open-ended sit-in from 3 pm (1300 GMT) on Friday for a national unity government," said an opposition statement.

"The opposition forces appeal to demonstrators to brandish only the Lebanese flag and authorized slogans," the statement added.

Hezbollah leader Hassan Nasrallah, whose political stock rose sharply after the resistance put up by his movement's fighters to Israel's devastating summer offensive, called for a massive turnout.

"We appeal to all Lebanese, from every region and political movement, to take part in a peaceful and civilized demonstration on Friday to rid us of an incapable government that has failed in its mission," he said in a television broadcast greeted with shots in the air in parts of the capital.

But Siniora vowed late Thursday that his cabinet will fight against the return of any foreign tutelage on the country, in an apparent reference to Syria's military domination in Lebanon which ended in April 2005.

"The government of the independence ... will continue to defend freedom and the democratic regime which are targeted," he said in a televised address to the nation.

"We will not allow any coup against our democratic regime. We are determined to stay the course, as our government is legitimate and constitutional ... and enjoys the confidence of parliament," he said.

Siniora said his government was determined to protect the opposition's "peaceful" demonstrations, "but we will not accept any security breach or any aggression on private or public properties."

Telecommunications Minister Marwan Hamadeh also made clear that the government had no intention of giving in to pressure from the street.

Hamadeh also renewed the cabinet's criticism of pro-Damascus President Emile Lahoud, whose term in office was extended until next year through a controversial Syrian-inspired constitutional amendment in 2004.

The six pro-Syrian ministers in the cabinet pulled out two weeks ago in protest at the failure of cross-party talks to agree to their demands for a national unity government, including an allied faction then already in opposition.

The opposition factions had threatened to take to the streets last week but postponed their plans after the November 21 assassination of anti-Syrian industry minister Pierre Gemayel, the sixth Damascus critic to be killed in the past two years.

His funeral instead brought hundreds of thousands of government supporters on to the streets two days later in an outpouring of anger at neighbouring Syria and its allies among the opposition, including Shiite Hezbollah.

As well as Hezbollah, the opposition factions include the Shiite Amal party of parliament speaker Nabih Berri, the Christian faction of former prime minister Michel Aoun and supporters of the pro-Syrian president.

Lebanon's feuding pro- and anti-Syrian factions have reached a dangerous deadlock that threatens to paralyse all state institutions.

The key pro-Syrian officials in Lebanon's power-sharing regime -- the president and the parliament speaker -- do not recognize the rump anti-Damascus cabinet left by the pullout of Syria's allies.

The pro-Western cabinet in turn challenges the legitimacy of the president.

Amid the tensions, Lebanese army chief General Michel Sleiman on Wednesday called on his men to "stand ready" to maintain public order in case of mass demonstrations.

"The army will not tolerate any damage to public property or any clashes. It considers it stands at an equal distance from both sides," he said.

And Maronite Catholic Cardinal Nasrallah Sfeir, head of Lebanon's largest Christian community, on Thursday criticised plans to hold demonstrations "which have never been a way to resolve any problem."

"We can only resolve matters through honest and sincere dialogue," he told hundreds of black-clad women from the anti-Syrian ruling majority at the Maronite patriarchate northeast of Beirut.

During the protest Pierre Gemayel's mother, Joyce, called on all Christians to refrain from taking part in the demonstration.

"Any Christian who demonstrates on Friday will be digging Lebanon's grave," she said to loud applause. -AFP