The conference will break up for a day, she said, and reconvene on Jan. 24 in Geneva for the start of actual negotiations between Syrian President Bashar Assad's government and armed Syrian opposition groups.
Mattar said the negotiators would set the timeframe for the negotiations at the start and continue working through the weekend—and around the clock—until they are finished.
Brahimi is to meet on Friday with U.S. and Russian envoys to make final preparations for the conference including the selection of which nations will be invited.