Key rebel leaders have called for a Darfur peace conference to be canceled as U.N. and African mediators bid for more time to draw them into the talks, which stalled just after opening.

The two main rebel chiefs are boycotting the U.N. and African Union-brokered conference, saying they will not sit with minor rebel factions they describe as government stooges.

Jan Eliasson, the chief U.N. envoy, said U.N. Secretary General Ban Ki Moon had decided not to postpone the conference, which opened Oct. 27 in the Libyan coastal town of Sirte because all agreed a momentum had urgently to be launched to end the conflict.