"It is an important step, especially as the idea for such an operation came from the peace and security council of the African Union," a decision-making organ of the 15-member African body, a source at the AU Mission told AFP.
This council "has always insisted on the African character of such a force and of Sudan's approval of its mandate," the source said.
Speaking on condition of anonymity, the source said the next meeting -- scheduled for November 24 in Brazzaville -- will be essential in promoting the idea of a hybrid force to maintain peace in Darfur.
In a statement released after hours of discussions on Thursday with AU, Arab League and African officials at the Addis Ababa headquarters of the AU, United Nations chief Kofi Annan said the proposed transformation of the current AU mission into one involving the world body had been agreed by Sudan.
But Sudanese Foreign Minister Lam Akol said on Friday that the Addis Ababa accord does not include the deployment of UN troops.
"We must not speak of a joint force, because what we are discussing and what we have agreed on is an African Union force assisted by the United Nations," Akol told state-owned Omdurman radio.
Akol's statement falls in line with Khartoum's position of rejecting UN peacekeeping troops in Darfur, although Sudan has signalled that it was open to the idea of logistical and financial support from the UN for the AU mission.
On the eve of Thursday's meeting, Sudanese Vice President Ali Othman Mohammed Taha stressed that if Khartoum were to accept Annan's proposal, it would insist on the Darfur mission being under African command.
Sudan's ambassador to Addis Ababa, Said Ali Hassan, said in statements to the Sudanese news agency SUNA that the parties agreed to implement two stages out of the three stages of the plan.
The first stage, he said, would provide 22 million dollars to AMIS, and the second stage would give 55 million dollars to support the African mission in the region.
Abdulmuhammad Abdulhaleem, Sudan's UN envoy, said the proposal could bring an end to the idea of a 20,000-strong peacekeeping force, as called for by UN Security Council Resolution 1706 adopted on August 31.
"This is a new plan that can be largely accepted by Sudan and takes 1706 to the graveyard," Abdulhaleem said. "1706 is dead."
On Friday, US National Security Council spokesman Gordon Johndroe said US President George W. Bush, whose administration has accused Khartoum of genocide, "welcomes the agreement".
"This agreement paves the way for a joint AUUN peacekeeping force for Darfur composed primarily of and led by Africans, and commanded, supported and funded by the UN," he said.
Sudanese ally Egypt also welcomed the hybrid force on Friday.
The war in Darfur erupted in February 2003 when rebels from minority tribes took up arms to demand an equal share of national resources, prompting a heavy-handed crackdown from the government forces and a proxy militia called the Janjaweed.
The conflict left 200,000 people dead and displaced 2.5 million more, according to UN figures. Some sources give much higher figures.

Copyright AFP (Agence France-Presse), 2006