Rival Lebanese leaders reached a deal on Wednesday to end 18 months of political conflict that had pushed their country to the brink of a new civil war.

Delegates from the U.S.-backed ruling coalition and the Hezbollah-led opposition told Reuters disputes over a parliamentary election law and a new cabinet had been settled on the sixth day of Arab-mediated talks in Qatar.

The deal paves the way for parliament to elect army chief General Michel Suleiman as president, filling a post vacant since November because of the political deadlock. The vote could take place as early as Thursday, delegates said.

"The deal is done. The text has been written," an opposition delegate told Reuters.

The official announcement was expected at 10.00 a.m. (8 a.m. British time) at a ceremony attended by the Lebanese leaders and Arab mediators.

A ruling coalition delegate also confirmed the deal, which will meet the opposition's long-standing demand for veto power in cabinet.

Hezbollah, a group backed by Iran and Syria, increased pressure on the ruling alliance this month by routing its followers in a military campaign. The Qatari-led negotiations in Doha built on mediation that ended violence which killed 81.

It was Lebanon's worst civil conflict since the 1975-1990 war and exacerbated tensions between Shi'ites loyal to Hezbollah and Druze and Sunni followers of the ruling coalition.

Qatari Emir Sheikh Hamad bin Khalifa al-Thani joined the Doha talks shortly before midnight after returning from Saudi Arabia - one of the main foreign backers of the ruling coalition.

INCREASING THE PRESSURE

The anti-Damascus ruling coalition had long refused to meet the opposition's demand for cabinet veto power, saying the opposition was trying to restore Syrian control of Lebanon.

Syria, a close ally of Iran, was forced to withdraw troops from Lebanon in 2005 following the assassination of former Prime Minister Rafik al-Hariri.

The United States held up the withdrawal as a foreign policy success story. But the Hezbollah-led opposition has steadily been increasing pressure on Washington's allies in Lebanon.

Opposition ministers quit the cabinet of Prime Minister Fouad Siniora in November, 2006 in protest at the governing alliance's refusal to meet the demand for veto power.

The resignations stripped the cabinet of all its Shi'ite ministers and upset Lebanon's delicate sectarian power-sharing system.

Hezbollah's military campaign this month further increased pressure on the ruling alliance and forced the government to rescind two measures targeting the Iranian-backed group and which had triggered its escalation.

The opposition has said that under a deal it will remove a protest encampment that has paralysed Beirut's central commercial district since December, 2006 and was erected as part of its protest campaign.

The deal will include a pledge by both sides not to use violence in political disputes, echoing a paragraph in an agreement drafted in Beirut that ended the fighting.