Attacks in West Darfur have killed at least 63 people, half of them children, as rebels on Friday accused Khartoum of remobilising Arab militia after suffering two military defeats on the Sudan-Chad border.
"The government have begun mobilising the Janjaweed widely, especially in West Darfur, because they want to clear the area and move north along the border and defeat us," said Bahr Idriss Abu Garda, a leader of the National Redemption Front (NRF).
Rebels from the NRF alliance said of the 63 dead, 33 were children. The United Nations said 27 of those were under 12 and urged the government to protect civilians.
A struggling African Union force, monitoring a widely ignored peace deal, said up to 92 people may have been killed in the attack on October 29 on at least four villages in the Jabel Moun area, where rebel and government forces are present.
AU soldiers said the government was also bombing regularly in the area around and north of Tine town on the Sudan-Chad border. The last bombardment was on October 23.
Sudanese officials deny the reports saying they have not mobilised Arab militia and the army denies using its Antonov planes, which would be a violation of a UN Security Council resolution.
Experts estimate 200,000 people have been killed and 2.5 million forced from their homes in 3-1/2 years of revolt in Darfur.
Mostly non-Arab rebels took up arms accusing central government of neglect.
Khartoum turned to militias, known locally as Janjaweed and mainly from Arab tribes, to quell the revolt.
Those militia stand accused of a widespread campaign of rape, murder and looting, which Washington calls genocide.
The government denies genocide but the International Criminal Court is investigating alleged war crimes in Darfur.
Sudanese President Omar Hassan al-Bashir on Friday indicated the toll in Darfur had been exaggerated saying only 10,000 people had died in western Sudan.
At a news conference in Beijing where he was attending a summit of African leaders, he reiterated that he would not allow UN forces into Darfur, despite a UN resolution authorising 22,000 UN troops to replace AU peacekeepers.
"We decided that with such an army moving into our country, the impact is going to be the same as what's been happening in Iraq," Bashir said.
China, which has close business and diplomatic ties to Sudan, is a veto-wielding member of the Security Council and has been accused by human rights groups of protecting Sudan against any strong action over Darfur.
But at the Beijing meeting, Chinese President Hu Jintao appeared to be nudging Bashir towards accommodation.
"The Darfur issue is again at a critical juncture," Chinese State television quoted him saying on Thursday.
An AU-brokered peace deal in May signed by the government and one of three rebel negotiating factions has seen little implementation.
A government plan to disarm the Janjaweed by October 22 has not occurred and a new rebel alliance renewed hostilities with the government.
In fact since the deal was signed to much fanfare in Abuja, Nigeria, violence has only increased and a new war has broken out in North Darfur.
The NRF defeated the government in two major battles in the past two months, top UN envoy Jan Pronk said. He was expelled for saying army morale was low, generals had been sacked and soldiers were refusing to fight in North Darfur.
Abu Garda said that was why the government was mobilising the militia.
Acting sector commander of Tine base, Thomas Chaona, said Antonovs could be seen or heard flying almost daily along the Chad-Sudan border and on October 13 an AU patrol was almost bombed because the pilot mistook them for a rebel convoy.
"October 13 we sent a patrol out ... it was threatened that the patrol should pull back to the camp because the Antonov was up and that Antonov was about to release bombs on our patrol," he said.