DAMASCUS, Syria — The Syrian government and the main umbrella for Syrian opposition and rebel groups announced Tuesday their conditional acceptance of a proposed U.S.-Russian cease fire that the international community hopes will bring them back to the negotiating table in Geneva for talks to end the war.

The announcement came after the United States and Russia agreed on a new cease-fire for Syria that will take effect Saturday, even as major questions over enforcement were left unresolved.

The Syrian Foreign Ministry said in a statement Tuesday that it accepts the proposed truce, adding that operations will continue against the Islamic State group, al-Qaida’s branch in Syria and “other terrorist groups linked to them.”

“The Syrian government stresses the right of its armed forces to retaliate against any violation carried out by these groups,” the ministry’s statement said.

The Syrian announcement came after the main umbrella for Syrian opposition and rebel groups, the High Negotiations Committee, said late Monday that it “agrees to a temporary truce” as long as the main opposition’s demands are met.

The HNC said the “acceptance of the truce is conditional” to the Syrian government ending its siege of 18 rebel-held areas, releasing detainees and the cessation of aerial and artillery bombardment.