The Sudanese government and rebel leaders have signed an agreement on security and humanitarian issues in the troubled Darfur region.
The agreement was signed after two weeks of African Union-mediated peace talks in Abuja, Nigeria.
In a major concession, the Sudanese government has agreed to establish a no-fly zone over Darfur. The government and the two main rebel factions also pledge to allow unrestricted access to the region by humanitarian relief agencies.
Nigerian President Olusegun Obasanjo called the breakthrough a step in the right direction, although he cautioned that more work needs to be done.
The signing occurred a week before a special U.N. Security Council meeting on the Darfur crisis in Nairobi, where sanctions against the Sudanese oil industry could be considered.
U.N. officials say the Darfur conflict has created the world's worst humanitarian crisis, with more than one-and-one-half-million people driven from their homes and tens-of-thousands killed.
Two black rebel groups took up arms against the ethnic-Arab Sudanese government early last year, saying the government had ignored Darfur's needs. In response, Arab militiamen called Janjaweed attacked black villages across the region.
Residents and aid workers say the Sudanese military provided air support for the raids - making the no-fly agreement particularly important. The African Union is moving about three-thousand troops and police officers to the region to monitor a ceasefire.