Syrian opposition groups have agreed in principle on a plan to unite against President Bashar Assad, participants told reporters in Doha Saturday night.

“We have agreed on the main points of the formation of a Syrian national coalition for the forces of the opposition and the revolution. We will continue our discussions on the details on Sunday,” opposition figure Suhair Atassi told AFP.

Competing opposition groups are in Doha for Western-backed talks aimed at forging a new opposition leadership group in an effort to oust Assad and prepare the ground for a smooth transition following his removal from power.

The groups aim to form a transition government in rebel-held areas which would likely serve as a conduit for foreign aid to the opposition. The rebels’ Western backers have declined to send weapons to the rebels, for fear they will fall into the wrong hands.

Syria’s opposition says it needs weapons to break the military stalemate in Syria and defeat Assad. Asked Friday what he wants from the international community, George Sabra, head of the Syrian National Council, the largest opposition group said: “Weapons, weapons, weapons.”

Earlier Saturday, two suicide car bombers struck a military camp in the southern city of Daraa on Saturday, killing at least 20 government soldiers and prompting clashes in the area.

Bombings targeting state security institutions have become frequent in recent months, raising Western fears that extremists fighting with the rebels could gain influence.