The situation in Sudan’s disputed Abyei region has worsened with armed looters setting fires in abandoned towns.
North Sudanese forces took control of Abyei at the weekend, claiming they were driving out southern troops they said had illegally moved in.
The oil-rich region is the main sticking point in the separation of Sudan after the south voted for independence in January.
President Omar Bashir says he wants a peaceful solution to the crisis.
But his Minister of State for Presidential Affairs, Amin Hassan Omar, insisted it had been the northern army’s duty to enter Abyei, to keep the peace and expel southern forces.
The United Nations Security Council has condemned the violence, including an attack on a UN convoy on Thursday.
Analysts fear the dispute over Abyei could drag Sudan – which is due to separate in July – back into a civil war.