A Sudanese government official in Khartoum confirmed on Friday that the army was still in the border region, which it occupied in May. But she insisted it would withdraw after the full deployment of the Ethiopian peacekeeping force (UNISFA), less than half of which has arrived so far, according to the United Nations.

"Today is September 30, the day agreed by the parties for the full withdrawal of all forces from Abyei area except the United Nations security forces," Luka Biong Deng, a senior leader of South Sudan ruling party, said in a statement.

"The government of Sudan has, for a second time, cancelled today the Abyei Joint Oversight Committee (AJOC) meeting, confirming suspicions that all along its primary concern was not to withdraw its forces from Abyei," he added.

"The government of Sudan ... is doing all it can to paralyse (AJOC)'s ability to act," and is clearly determined to continue its occupation and ensure that Abyei's "true residents" never return, said Biong Deng, who hails from the region.

The fertile border district, which is claimed by north and south, was mainly inhabited by the ethnically southern Ngok Dinka people until May, when it was overrun by the Sudanese army.

The move prompted more than 110,000 residents to flee south and soured relations between Juba and Khartoum in the run up to the formal independence of South Sudan on July 9.

Arab Misseriya nomads, a northern-backed tribe who migrate south each year, are said to have moved into Abyei town with the Sudanese troops.

On September 8, under an agreement brokered by the UN and African Union in Addis Ababa, the two governments pledged to redeploy their troops by the end of this month outside the fiercely disputed region, where a new peacekeeping force is now in place.
A UN spokesman in New York said less than half of the planned 4,200 Ethiopian peacekeepers were now in Abyei, but claimed there was no correlation between Sudan's delayed troop pull-out and the deployment of the peacekeepers.

"The withdrawal is not contingent on the deployment," Martin Nesirky said, making a new appeal to Sudan and South Sudan to remove their troops from the tense border region.

However, Sudan's deputy information minister, Sanaa Hamad, told AFP the Sudanese soldiers would only do so "after the Ethiopian peacekeepers complete their deployment."

Biong Deng said on Friday that he and Edward Lino, the two southern members of the Abyei Joint Oversight Committee, would visit the region anyway and meet the UNISFA forces, to make an assessment of the conditions for the return of Abyei's displaced residents.

"People are suffering and the unthinkable would be for the south to let the north's unilateral actions hamper the return of displaced people of Abyei area to their home areas," he added.