Amr Moussa, the chief of the Arab League, has been in Beirut to end the political deadlock between the Western-backed ruling majority and the opposition, backed by Syria and Iran.
"The Arab initiative has not hit a wall. Rather, perhaps it has reached a closed door that can be opened," said Moussa.
The Arab plan calls for General Michel Suleiman, the army chief, to be elected as president, the formation of a national unity government in which no one party has veto power, and the adoption of a new electoral law.
Rival Lebanese leaders have agreed on Suleiman as the candidate to fill the presidency but are at odds over the make up of the government.
The ruling majority has accepted the bid but the Hezbollah-led opposition is demanding it be granted a third of the seats in a new government so the opposition can have veto power.
The political deadlock is the worst crisis in Lebanon since its 1975-1990 civil war.