Authorities in the north and south of Sudan have reached an agreement on an administration for the disputed oil-rich region of Abyei, where clashes earlier this year had threatened to derail a 2005 peace deal.

A spokesman for Omar al-Bashir, Sudan's president, said on Fridaythat a southerner had been appointed to head the interim administration of the region.

Arop Moyak, a member of the southern Sudan's People Liberation Movement (SPLM), has been named head of Abyei's administration, and his deputy Rahama Abdel Rahman al-Nour, would be the representative for the northern National Congress Party (NCP), Mahjub Faidul, spokesman said.

Fighting between northern and southern troops in May threatened the country's fragile peace and drove 50,000 people from their homes.

After the fighting in May, the two sides agreed to a roadmap to resolve the crisis with a joint force to patrol the area and discussions on how the region would be run.

Dirdiri Mohamed Ahmed, northern National Congress Party official said on Friday: "We can state confidently that we have managed to finally clear this hurdle in the way of implementing the comprehensive peace agreement."

Yasir Arman, a senior SPLM official, confirmed the agreement.

Unresolved issues

The borders of the region, as well as whether it was part of north or south Sudan, were left unresolved under the 2005 peace deal which ended Sudan's 21-year-long civil war.

The north-south peace deal in 2005 ended Africa's longest civil war and created separate north and south armies.

Faidul said that the development is an "important step" in settling the Abyei dispute, but it should not predetermine the result of or influence international arbitration on the region.

Derek Plumbly, the head of the international body tasked with monitoring the north-south deal, praised the agreement after "very delicately balanced negotiations."

"This was the main single outstanding element in the roadmap that was agreed after the fighting in May," he said.

"It means that the donor community will be able to move in and support the return of the people and support the administration in reconstruction."

Secession vote

Moyak is from the Dinka Ngok which traditionally inhabit the region and al-Nour is from the nomadic Misseriya tribe.

There have previously been disputes over whether the Misseriya were residents of Abyei.

People in the south and Abyei will able vote in 2011 on possible secession therefore which tribes are resident is a key issue.

The issue of Abyei's borders has been referred to The Hague-based Permanent Court for Arbitration for final decision.

The oil wells in Abyei have fuelled an economic boom in Sudan, Africa's biggest country.