Updated

The United Nations has extended the mission of the joint U.N.-Arab League envoy to Syria through the end of the year.

U.N. spokesman Martin Nesirky announced Thursday that Lakhdar Brahimi's contract has been renewed through the rest of 2013. It had been set to expire Friday.

International efforts to end Syria's war have so far failed. The U.N. says at least 60,000 people have been killed and millions have fled.

Brahimi said last week that an opposition offer to negotiate "challenges the Syrian government to fulfill its often-repeated assertion that it is ready for dialogue and a peaceful settlement."

Syria has accused Brahimi of exhibiting "flagrant bias" after the Algerian diplomat called for real change in Syria and said President Bashar Assad was resisting his people's aspirations.