Abdulrahman Zuma, a government spokesman, said Sudan was considering US changes to a draft agreement, increasing the number of rebels that would be integrated into its security forces.

It would also look at a swifter disarming of the Janjawid militia, accused of atrocities against civilians in the Darfur region, he said.

"Through this so-called American initiative, it seems that the government is going to make some concessions, especially about reintegration and disarmament," Zuma said.

Robert B Zoellick, the US deputy secretary of state, flew on Tuesday to Abuja, the Nigerian capital where the talks are being held, in an effort to break the deadlock.

The US and Britain, along with the African Union, have until midnight local time on Thursday to forge an agreement between the two sides.

Push for solution

Sudan's government had agreed to a peace proposal from African Union mediators, but it was turned down by three Darfurian rebel factions demanding better proposals on security, power- and wealth-sharing.

Denis Sassou-Nguesso, president of the Republic of Congo and current head of the AU, and other African leaders were also expected to arrive in Nigeria later on Wednesday to add to the push for a solution.

The conflict began when rebel groups including the Sudan Liberation Army and the Justice and Equality Movement, representing mostly non-Arab tribes, took up arms in early 2003, accusing the Arab-dominated government of neglect.

Khartoum responded by providing arms to the predominantly Arab militia, known as Janjawid, whose campaign of murder, arson rape and looting has left tens of thousands of people dead and more than two million displaced.

Khartoum denies responsibility.