KHARTOUM (Reuters) -Sudan’s government has launched a major offensive in North Darfur despite an agreement to restart a peace process, Darfur rebels said on Sunday.

A rebel commander said clashes continued on Saturday and Sunday, following joint attacks by government and militia forces on rebel bases in the Bir Mazza area on November 15-16.

The African Union (AU) monitoring mission, which had condemned last week’s attacks, confirmed that fighting was continuing in the area. But the Sudanese army denied it was conducting an offensive.

“We have split into two or three groups and all have fighting,” said Jar el-Neby, a rebel commander from the National Redemption Front (NRF), which rejects a May peace accord signed by only one of many rebel factions.

“The government did not use planes yesterday but today the Antonovs are circling,” he told Reuters from Darfur.

Government and allied militia known as Janjaweed were still inside the former rebel town Bir Mazza, he said and called on the international community to intervene to protect civilians there.

“We have confirmed at least six people killed and more attacks on civilians and looting of cattle is going on,” Neby said.

The AU confirmed the continued fighting. “It’s an open secret,” said one AU official.

But a Sudanese army spokesman denied the allegations.

“There were clashes between some tribes and the rebels in the area and the armed forces intervened just to protect the civilians there,” he said. “But the clashes were very minor, the (rebel) and AU reports are untrue.”

Experts estimate that some 200,000 people have been killed and 2.5 million forced from their homes in 3-1/2 years of conflict in Darfur. Mostly non-Arab rebels took up arms in early 2003 accusing the government of marginalising the remote west.

Khartoum mobilized tribal militias to stem the violence. Those militias now stand accused of a campaign of rape, murder and pillage.

The North Darfur clashes follow a refusal by Sudanese authorities to allow U.N. humanitarian chief Jan Egeland to visit areas near the fighting last week, despite Khartoum’s public insistence security is good in the region.

Foreign journalists have also been denied travel permits.

In the Ethiopian capital Addis Ababa on Thursday, Khartoum agreed to reopen political talks with Darfur rebels who had not signed the May deal.

But the rebels said the government was merely trying to buy time to press on with its military operations. A struggling, ill-equipped AU force has failed to halt the violence.

U.N. Secretary-General Kofi Annan said in Addis Ababa that Sudan had agreed in principle to a joint U.N.-AU force in Darfur, but Sudanese officials later denied any such agreement.