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 of tough negotiations led by former South African president Thabo Mbeki. It calls for the complete demilitarization of the region 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 be comprised of two members from both sides along with a representative from the African Union.

Mr. Mbeki told reporters the deal clears 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.

U.S. Secretary of State Hillary Clinton said the agreement was an important first step, but she says the true test will be compliance to the accord in the coming days.

Secretary Clinton says the Sudanese leaders are urged to follow through on their commitment to withdraw their troops and end all hostilities immediately.

She says both sides should also allow humanitarian aides unrestricted access to those in need.

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 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 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.

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.