DOHA - International peace envoy Kofi Annan warned on Saturday that Syria was slipping into "all-out" war, and a Syrian opposition figure said Russia had become part of the problem and should urge President Bashar Assad to quit power."The specter of an all-out war, with an alarming sectarian dimension, grows by the day," Annan told a meeting of members of the Arab League, co-sponsor with the United Nations of a peace plan aimed at ending the bloodshed in Syria.The fighting continued on Saturday as Syrian rebels fighting to oust Assad killed six soldiers in the southern province of Deraa and at least eight others in clashes on the outskirts of the capital Damascus, a monitoring group reported."There were heavy clashes between Syrian forces and fighters from the opposition in (Deraa)... resulting in the death of at least 6 Syrian troops," the British-based Syrian Observatory for Human Rights said in a statement."At dawn, there were violent clashes in al-Ghouta (near Damascus), killing at least eight Syrian troops," it added.The Observatory said that two civilians were also killed on Saturday, one during army raids in Damascus and one by gunfire in the central city of Homs, where activists say the army has been waging a shelling offensive on opposition districts.Burhan Ghalioun of the Syrian National Council, the divided body claiming to speak for political opposition to Assad, said: "With its support of the regime and for Assad remaining, Russia has become part of the problem rather than part of the solution. If it cooperates to find a formula that makes Assad leave, it will become part of the solution."Prime Minister Sheikh Hamad bin Jassim al-Thani of Qatar - which has backed arming Sunni Muslim insurgents fighting to topple Assad, a member of Syria's minority Alawite sect - said Annan should set a time limit for his mission.He also called on the UN Security Council to put Annan's plan - based on a ceasefire that has yet to take hold, and that is meant to lead to a negotiated end to the Syrian crisis - under Chapter 7 of the UN charter, a measure that could authorise the use of force."We want the Security Council to refer the six-point (Annan) plan to a Chapter 7 resolution. We, the international community, cannot accept the situation to continue as it is," he said.