The United Nations says it wants to bring together Syria's warring parties on January 25 to begin talks to end nearly five years of civil war.
A spokesman for UN Syria mediator Staffan de Mistura said in a December 26 statement that de Mistura wants "the broadest possible spectrum of the Syrian opposition and others" at the talks in Geneva.
“Continuing developments on the ground should not be allowed to derail” the talks, a statement said.
The statement was issued one day after a top Syrian rebel leader was killed in an air strike on the outskirts of Damascus. The death of Zahran Allush, who led one of the most-powerful groups battling President Bashar al-Assad's forces, dealt a significant setback to the opposition.
The UN Security Council unanimously approved a resolution on December 18 endorsing a road map for a Syria peace process, in a rare show of unity among major powers.
More than 250,000 people have been killed in the war that grew out of a Syrian government crackdown on a pro-democracy movement in early 2011.
Islamic State militants have used the chaos to seize territory in Syria and Iraq, and some 4.3 million Syrians have fled.
Based on reporting by AP, Reuters, and AFP