Heads of state from Egypt, Chad, Eritrea, Nigeria and Sudan are taking part in the summit convened by Libyan leader Moamer Kadhafi, which also includes officials from the African Union (AU), charged with observing a shaky April 2004 ceasefire.

Sudanese Foreign Minister Mustafa Osman Ismail said he hoped the summit, due to open in the afternoon, "will be the occasion to confirm our commitment to maintaining a ceasefire and respecting our agreements with rebels."

"We hope that a calendar will be decided for a resumption of negotiations that will lead to a political solution," Ismail told AFP in Tripoli.

"If the summit is a success, we will be able to draw a new political map according to which people from Darfur will enjoy political participation and the country's wealth," he added.

The two main ethnic rebel groups, the Sudan Liberation Movement (SLM) and the Justice and Equality Movement (JEM), have accused the Arab-dominated regime in Khartoum of pursuing a "war of extermination" against Darfur's indigenous minorities since they launched an uprising two years ago.

Marked by mass killings, torture, rape and pillage, the campaign has left more than 300,000 dead and 2.4 million people displaced, according to a British parliamentary report.

The SLM urged Khartoum in a statement Monday to "implement all United Nations' resolutions" so that "Sudan does not become a safe haven for criminals."

The UN Security Council demanded last March the prosecution in the International Court of Justice of presumed war criminals in Darfur, including top Sudanese government officials.

But Sudan's President Omar el-Beshir, which will attend Monday's summit, has vowed not to hand over any Sudanese nationals to the world court, arguing that his country's courts are competent.

And Ismail denied Monday any ties with the Janjaweed militia, which Darfur rebels say are backed by Khartoum, branding them "a band of thugs and thieves."

The SLM also reiterated his "readiness for serious and responsible negotiations in Abuja (Nigeria) under the auspices of the African Union."

It underscored its "commitment to the implementation of all agreements clinched with Khartoum, including the ceasefire."

Peace talks sponsored in Abuja by the AU between the Sudanese government and the rebels have been suspended since December because of repeated violations of the ceasefire signed under the mediation of Chad in April last year.

"Negotiations must be resumed to reach a political resolution and allow the people in Darfur to become partners in Sudan and enjoy their rights while fulfilling their obligations," Egyptian Foreign Minister Ahmed Abul Gheit was quoted as saying by Egypt's official news agency MENA.

He said his country favored "the respect for the unity, territorial integrity and sovereignty of Sudan."

Beside Kadhafi and Beshir, Chadian President Idriss Deby, Nigerian President Olusegun Obasanjo, Eritrean President Isaias Afeworki and Egypt's President Hosni Mubarak are set to attend the meeting.

Libyan authorities said the participation of Gabon's President Omar Bongo Ondimba, which was announced earlier last week, was no longer certain.