The opposition wants enough seats in the new government to give it veto power over cabinet decisions, a plan rejected by the March 14 bloc.
He said that both sides shared broad agreement on the need for changes to the country's electoral law.
Lebanese deputies were due to hold a session on Tuesday to elect a new president. But the parliamentary speaker announced on Monday that the vote had been postponed - for the 15th time - to March 11.
The March 14 bloc and the Hezbollah-led opposition have been locked in a bitter power struggle since November 2006, when Hezbollah and its allies pulled its members out of the March 14-led cabinet.
|Suleiman is yet to be voted into power by |
Lebanon's feuding factions [AFP]
Relations between the two sides have further deteriorated since the presidential term of Emile Lahoud, who is widely perceived to be a pro-Syrian figure, ended in November 2007.
The March 14 bloc, which is widely considered to be pro-Western in its outlook, and Hezbollah, which has close links to Syria and Iran, have agreed on a consensus president in principle.
However, the opposition has so far boycotted parliamentary meetings to formally elected the consensus candidate, General Michel Suleiman, who is chief of the Lebanese army.
The opposition cites the failure to get veto rights in the cabinet as the reason for its boycott.
Moussa's talks in Lebanon came after a weekend meeting in Riyadh between the leaders of Egypt and Saudi Arabia, who both support the government of Fouad Siniora, Lebanon's prime minister.
The pan-Arab Al Hayat
daily reported on Monday that Hosni Mubarak, Egypt's president, and King Abdullah of Saudi Arabia said a new Lebanese president should be chosen before an Arab League summit in Syria in late March.
Ahmed Aboul Gheit, Egypt's foreign minister, said last month that the success of the Damascus meeting was largely dependent largely on Lebanese leaders agreeing on a new president.
The US and the March 14 bloc say that Syria has sought to block the presidential election, a charge denied by Damascus.