Sudan says the African Union must pull its peacekeepers from Darfur by September 30 if it continues to support a U.N. takeover of the mission.
A Sudanese foreign affairs representative, El-Wasilla Al Samani, spoke to reporters Wednesday after meeting with AU officials in Addis Ababa.
The AU has signaled a readiness to hand over its Darfur mission to U.N. control. But Sudan's government has said it will fight any U.N. peacekeepers who enter the war-torn region.
Seven-thousand African peacekeepers have not been able to keep the peace in Darfur, where more than three years of fighting has killed an estimated 200,000 people.
The U.N. Security Council has approved plans to absorb the AU force and expand it to 20,000 troops.
On Tuesday, the U.N.'s humanitarian chief, Jan Egeland, urged Khartoum to accept the U.N. mission. Egeland warned that growing insecurity in Darfur could force most aid agencies to withdraw and leave hundreds of thousands of people without any assistance.
Some information for this report was provided by AFP and AP.