Two Arab tribes which have been battling off-and-on for months in Sudan's Darfur region have resumed fighting, leaving dozens dead, one of their leaders said on Friday.

Tribal disputes in the Darfur region have been driven by conflict over resources including land, water and mineral rights, but it was not immediately clear what triggered the latest fighting.

"Yesterday the Salamat attacked one of our villages... and we clashed with them. "In total, 51 people were killed and 65 were injured," Ahmed Khiri, a Misseriya tribal leader, told AFP.

Thursday's battle happened in the Umm Dukhun area of Darfur's southwest, he added.

A leader of the rival Salamat tribe, who asked not to be named, confirmed that deadly fighting took place but gave no casualty figures.

"We lost a number of men and also there were losses among the Misseriya," he said.