The Sudanese government and the United Nations have signed an agreement Wednesday to boost humanitarian work in the volatile Darfur region.
Under the agreement, Khartoum is expected to give better access to aid groups trying to operate in Darfur.
U.N. humanitarian chief John Holmes toured Darfur this week and warned that the effort to aid refugees is fragile and could fail if the situation in the western region deteriorates.
Meanwhile, Sudanese President Omar al-Bashir has underlined his rejection of U.N. efforts to send a peacekeeping force into Darfur.
He told the Arab summit in Saudia Arabia Wednesday that Sudan would only accept financial and logistic support from the United Nations.
An ill-equipped African Union force has not been able to stop the violence in Darfur.
Fighting between Darfur rebels and militias backed by the Sudanese government has killed more than 200,000 people and displaced at least two million since 2003.
Some information for this report was provided by AP and Reuters.