GENEVA — A top U.N. official says he hopes that the U.N.-brokered cease-fire in Syria will take place, but he warns that there are no guarantees it will hold.

The 15-nation U.N. Security Council endorsed the idea of a temporary truce, proposed by the U.N.-Arab League envoy to Syria with the aim of setting up talks on ending the country's 19-month-old conflict.

"We hope that they both realize the importance of a pause in the fighting ... in the symbolic quieting the silence of the guns," said Jan Eliasson Eliasson, the U.N. Deputy Secretary-General. "But the most important thing is that it could perhaps create a political environment, where political talks are possible," he said Thursday.

Lakhdar Brahimi, the envoy, has warned that the failure of yet another U.N. cease-fire plan would only worsen the fighting.