A United Nations official say recent violence in Sudan's troubled Darfur region has left at least 40,000 civilians displaced.

The head of the U.N. Office for the Coordination of Humanitarian Affairs in northern Darfur, Gregory Alex, says many of these newly displaced are living in the desert with no shelter.

Last month, rebels in Darfur said government forces and allied militias launched a series of heavy ground and air assaults on their positions in northern Darfur.

Government officials said troops in the area were only guarding roads to protect humanitarian convoys from rebel attacks.

Darfur rebels began an uprising against the Sudanese government in 2003.  U.N. experts estimate the five-year conflict has killed more than 200,000 people and displaced 2.5 million others. 

Sudan accuses Western governments and the media of exaggerating the size and scope of the conflict and says no more than 10,000 people have died.