Sudan said on Sunday leaders of a rebel group in its western Darfur region were making regular visits to Israel and ties with the Jewish state had caused a split in rebel ranks.
A rebel spokesman denied any link with Israel and said the charge was an attempt to stir up Muslim public opinion. An Israeli government source told Reuters the Sudanese statement was absurd.
Sudanese Foreign Minister Mustafa Osman Ismail told reporters in Cairo some leaders of the rebel Justice and Equality Movement (JEM) had split from the group two days ago over ties between its leadership and Israel.
The Islamist government in Khartoum has said 210 JEM rebels surrendered their arms in the Chadian-Sudanese border town of Tine on Friday, a report JEM denied.
Ismail said those who had broken away from the group, "confirmed that the leadership of the movement make regular visits to Israel".
JEM, one of two Darfur rebel groups, denied the accusation and said none of its leaders had split from the group.
"There is no relationship between the movement and Israel and I have no knowledge of any intention that there should be a relationship. It is lies on the part of the government," JEM Secretary-General Bahar Idriss Abu Garda told Reuters.
"The government is striving to mislead Arab and Islamic public opinion," he said. Sudan sought Arab help on Sunday to head off possible sanctions threatened by the United Nations if Khartoum fails to rein in marauding militiamen accused of genocide and ethnic cleansing in its western Darfur region.
Sudan has about three weeks left to show the UN Security Council it is serious about disarming the Janjaweed militia. Darfur rebels say Khartoum is backing Janjaweed attacks to drive non-Arab villagers from their homes.
Sudan's Foreign Minister Mustafa Osman Ismail said Khartoum was seeking political support from Arab ministers "which will lead to the halting of any attempts to target Sudan or issuing of sanctions against it".