BEIRUT (AFP) – Lebanon’s divided factions are aiming for a political compromise after mass protests led by the opposition overwhelmed Beirut and raised fears of a return to civil strife. The protracted deadlock has paralyzed the government,  opposition have clogged the capital in an escalating campaign to force a new national unity administration.

Arab diplomats were due in the capital to discuss a proposal with Prime Minister Fuad Siniora after securing the "agreement in principle" of  the opposition which launched a rally on Sunday the army said was "unprecedented" in size.Arab League envoy Mustafa Ismail was to hash out details of a proposal for the opposition’s participation in the government after its six ministers pulled out last month. Sunday’s huge protest in Beirut came on the 10th day of a thousands-strong sit-in on the government’s doorstep, and was countered by a pro-government rally in Lebanon’s second city of Tripoli.

The opposition has accused the government of being weak and corrupt and is demanding that Siniora’s cabinet make way for a government of national unity.Siniora has accused the opposition of trying to mount a "coup," and pledged that his government will overcome the crisis, while repeatedly urging a return to talks.

Ismail, whose visit on Monday is to be followed by Arab League chief Amr Mussa’s arrival on Tuesday, said he had secured the agreement of the opposition that it did "not want to bring down the government or block its work."

"The government in turn says ‘I welcome the opposition’s participation’… Hence, what we need is additional (discussion of) details of these guarantees."

Hezbollah MP Hassan Fadlallah confirmed that the movement’s leader Hassan Nasrallah had given a positive response to the Arab envoy.

"Nasrallah has informed Mustafa Ismail that Hezbollah sees positively any initiative that includes the formation of a government of national unity which secures a blocking minority," Fadlallah said.

"But in the end our position will be decided after being discussed among opposition leaders."

The protesters want to replace the current cabinet, formed after 2005 elections, with a national unity government that they say is required by the power-sharing arrangements in force since the end of the 1975-90 civil war.

The opposition has warned that if its demands are not met, it will form its own interim government and hold early elections, and has also hinted at other forms of civil disobedience including blocking main roads in the coming days.

The Arab League plan focuses on an "end to street protests… an agreement on forming a government that gives a blocking minority according to rules to be defined" and a "return to dialogue," the As-Safir daily said.

Agreement must also be reached on an international tribunal to try suspects in the murder of ex-premier Rafiq Hariri, parliamentary and presidential elections, and the holding of an international economic conference planned for January in Paris.

As-Safir said Hezbollah was demanding "the annulment of all unconstitutional decisions adopted by the government including its agreement to the UN text on the creation of an international tribunal."

Siniora’s coalition has accused the opposition of seeking to block cabinet endorsement of plans for an international tribunal to try suspects in the 2005 murder of Hariri, widely blamed on Syria.

Syrian President Bashar al-Assad, who has strongly denied any involvement in the killing, voiced his "commitment to Lebanon’s stability" and stressed that "Syria supports the decisions of the Lebanese," in talks with Ismail.

The Arab League envoy said the opposition had told him it "does not object to the creation of the tribunal, but only wants to be involved in the details".

However, the pro-Hezbollah Al-Akhbar daily cited opposition sources as being skeptical, saying the "mediation underway, however meritorious, does not provide a sufficient basis to speak of a solution to the conflict."