Negotiators for north and south Sudan have reached a landmark agreement on the future on the disputed oil-rich region of Abyei less than three weeks before the south is to gain its independence.

The accord was signed Monday in Addis Ababa, the Ethiopian capital, following days or tortured negotiations led by former South African President Thabo Mbeki. It calls for the complete demilitarization of Abyei and for the deployment of Ethiopian peacekeepers.

The north and south negotiators also agreed to establish a council to oversee security in Abyei. The council will comprise two members from both sides along with a representative from the African Union.

Mr. Mbeki told reporters the deal paves the way for the return of tens of thousands of displaced persons and establishes a basis for talks on Abyei's final status to be held after the south secedes on July 9.

Shortly after the agreement was signed, Mr. Mbeki briefed the U.N. Security Council by video conference. The council is to decide both the mandate and the size of the Ethiopian peacekeeping force.

The U.S. ambassador to the United Nations, Susan Rice, hailed the agreement and urged the immediate deployment of the Ethiopian peace-keepers.

Still to be negotiated is an end to weeks of fighting in the Sudanese border state of Southern Kordofan where government troops have been battling forces aligned to the south.

Talks to end the fighting there are taking place on Tuesday. But the VOA correspondent in Addis Ababa says hopes have faded for a humanitarian cease-fire that would allow emergency supplies to reach the nearly half a million Sudanese civilians trapped in the region.

Clashes in Southern Kordofan, which will remain under control of the north after the south secedes, began early this month when the Khartoum government sent troops into the region.

Ambassador Rice calls reports of the fighting there “horrifying.” She says reported attacks against civilians based on their ethnicity or political affiliation could “constitute war crime or crimes against humanity.”

The disputes in Abyei and Southern Kordofan have not only forced the displacement of more than 360,00 people, according to the United Nations, but also raised fears of a return to civil war.

North and south Sudan fought a decades-long civil war that ended in 2005 with an agreement providing for the south to hold a referendum on self-determination. Southern voters voted overwhelmingly in January to secede from the north.