Stalled peace talks between Darfur rebels and the Sudanese government may not restart this year, a senior African Union (AU) official has told the BBC.
There are now at least 12 rebel groups fighting in Darfur
Salim Ahmed Salim said negotiations could not restart without most of the key rebel factions on board.
Most of the key insurgent leaders boycotted the negotiations in Libya at the end of October and have still not said when they will return.
Mediators had hoped to have made some progress by the end of the year.
Some 200,000 people are estimated to have died and more than two million displaced during the four-and-a-half year war which has ravaged Darfur.
The AU Darfur envoy, Mr Salim, said there was no point resuming talks until most of the key rebel factions had agreed to take part.
He admitted that the boycotts had been a setback for the peace process.
"I don't think we need to have a fixation on a particular date. What we need to do is to have a fixation on having workable negotiations which can lead to an agreement," he told the BBC.
"But having said that, of course we also understand, this cannot be an endless process," he said.
Mr Salim, who's been leading the peace process with UN envoy Jan Eliasson, said they had been under immense pressure from the international community to get the talks started on 27 October, even though most of the rebels had said they would not attend.
Negotiations would be easier when a beefed-up force of UN and AU peacekeepers was on the ground, he said.
But the BBC's Amber Henshaw in the capital, Khartoum, says it is still unclear when that will be.
The deployment of the 26,000-strong force is scheduled to begin in six weeks, but could be delayed if helicopters and lorries are not received.
Earlier, the US accused the Sudanese government of "foot-dragging" over the deployment.
"Where we're deeply troubled and deeply disturbed, the concern can be laid primarily at the feet of the government of Sudan," US National Security Council spokesman Gordon Johndroe is quoted as saying by AFP news agency.