The information outlet affiliated with the government said the fighting between rebels of the Sudan Liberation Movement (SLM) and the Justice and Equality Movement (JEM) was prompted by a disagreement over command of forces.

It quoted Ismail Tur al-Jer, an SLM field commander, as saying hostilities erupted after he turned down a proposal to merge his forces with those of the JEM and place them under the command of a JEM officer.

He accused the JEM, a group the government has accused of having ties to jailed opposition leader Hasan al-Turabi, of promoting the agenda of organisations that "are distant from the Darfur issue".

Al-Turabi has previously denied the government's claims.

Many supporters of al-Turabi, a one-time ally of Sudanese President Umar al-Bashir, are in jail awaiting trial on an array of charges, including fuelling the 21-month conflict in Darfur and plotting to overthrow the government.

Tens of thousands of people have died, an estimated 1.45 million have been displaced from their homes and 200,000 have been forced into exile during the conflict.

The United Nations says the Darfur dispute has precipitated the world's worst humanitarian crisis.