Sudan has ordered two senior United Nations officials to leave, a UN spokesman said Thursday, after a recent spike in tensions between Khartoum and the peacekeeping mission in Darfur.

Sudan has ordered two senior United Nations officials to leave, a UN spokesman said Thursday, after a recent spike in tensions between Khartoum and the peacekeeping mission in Darfur.

The UN resident coordinator and humanitarian coordinator Ali Zaatari and the UN Development Program country director Yvonne Helle were asked by the government to leave, a UN staffer said.

Spokesman Stephane Dujarric said the UN has protested the expulsions.

"The UN has filed a protest with the government of Sudan following their decision to request the departure of two senior UN officials from the country," Dujarric told AFP.

It was unclear clear why the UN officials were asked to leave, or when they would have to exit the country.

The expulsions come as Sudan's government is locked in a dispute with the hybrid UN-African union mission in Darfur.