But U.N. diplomats, cautious after months of waffling by the Sudanese government, were not ready to celebrate.
The agreement came days before a Security Council mission to Khartoum to press for an end to the conflict in Darfur. At the end of a two-day summit of Sudanese, U.N. and African Union officials in Ethiopia, Sudan also agreed on the need for an immediate cease-fire and talks with rebel groups to end four years of fighting.
Sudan had initially agreed to the joint force in November but has backtracked and added conditions since then. Sudanese officials were still demanding yesterday that the force be made up of African troops with an African Union commander, preferences that U.N. peacekeeping officials say they will bear in mind but not be bound by.
Zalmay Khalilzad, the U.S. ambassador to the United Nations, said any conditions imposed on the peacekeeping force would be "unacceptable" and would be greeted with further international sanctions.
The United States strengthened its unilateral economic sanctions against Sudan last month.
U.N., African Union and Sudanese officials met in Addis Ababa, the Ethiopian capital, to jump-start a three-stage plan for a joint force to back up 7,000 overwhelmed AU troops deployed in Darfur. Sudan has agreed to the first two phases, accepting up to 3,000 police and troops by the end of the year to prepare for the new 23,000-strong force.
"We are fulfilling our commitments to the international community," said Abdalmahmood Abdalhaleem, Sudan's ambassador to the United Nations. "It is the turn of others to fulfill theirs and stop talking about threats and sanctions."
Khartoum has depicted the peacekeeping force as a "foreign occupation" and has insisted that the soldiers be African and be commanded by the AU, not the world body.
The force will be led by Martin Agwai, a Nigerian general who has served as a U.N. peacekeeping official. But the United Nations will not pay for a force it does not control and insists on overall command.
Peacekeeping officials say they will recruit soldiers first from African countries but will look elsewhere if there are not enough. The full force will take about a year to deploy, a senior peacekeeping official said.
"Our top priority is to get capable troops on the ground in Darfur," said Nick Birnback, a spokesman for the United Nations' peacekeeping department.
The push for soldiers to stabilize the region comes amid renewed diplomatic efforts. International experts say more than 200,000 people have been killed and more than 2 million displaced in four years of fighting between rebels and the Sudanese government over Darfur's resources and autonomy. The government says only 9,000 have died and denies any ties to militias that have carried out attacks on civilians.
Maggie Farley writes for the Los Angeles Times.