DAMASCUS — Syria's government Tuesday accepted a proposed U.S.-Russian cease-fire that is to go into effect later this week but reserved the right to respond to any violations of the truce. The main opposition and rebel umbrella group approved the deal but set its own conditions.
The developments followed an agreement between Washington and Moscow for a new cease-fire set to take effect at midnight Friday local time in the 5-year-old civil war, even as major questions over enforcement remain unresolved.
The truce does not cover the Islamic State, Syria's al-Qaida branch known as the Nusra Front or any other militia designated as a terrorist organization by the U.N. Security Council.
But exactly where along Syria's complicated front lines the fighting would stop and where counterterrorism operations could continue under the truce is still to be addressed. The five-page plan released by the State Department leaves open how cease-fire breaches would be dealt with.
While accepting the proposed truce, the Syrian Foreign Ministry said its operations will continue against ISIS, the Nusra Front and “other terrorist groups.” It stressed the right of its armed forces “to retaliate against any violation carried out by these groups.”
The main umbrella for Syrian opposition and rebel groups, the High Negotiations Committee, gave conditional approval late Monday. The HNC said acceptance was conditional on the government ending its siege of 18 rebel-held areas, releasing detainees and halting aerial and artillery bombardment.
However, Talal Sillo, a spokesman for the predominantly Kurdish Syria Democratic Forces, said that his group will not abide by the truce because it's fighting against the Islamic State group in northern Syria.

