Khartoum: The United Nations has so far found 89 bodies in the disputed oil-rich Abyei region of Sudan from fighting that erupted last month, a senior UN official said on Monday.

A joint north-south force is due to be deployed there this week after the clashes, which raised fears of a return to all-out civil war. Both north and south covet the central region, home to one of Sudan's two main oil fields.

The UN official, who declined to be named, said 89 bodies had been found in Abyei.

"Dead military are 68," the official said.

A joint north-south force had been due to deploy on Monday but that has now been put back to Tuesday because of administrative delays in flying them in on UN planes, said the force's commander, Valentino Tokmac.