Congo's president showed up unexpectedly at the Nonaligned Movement's summit Wednesday, raising hopes that negotiations could be held to halt the fighting in his central African country.

But President Laurent Kabila displayed his hostility toward mediation efforts by South Africa by skipping the official greeting offered by President Nelson Mandela to the 50 or so arriving heads of state.U.N. Secretary-General Kofi Annan, addressing the summit, appealed for Africa's leaders to solve their problems through political and not military means.

"For every day that we fail to do so, the innocent people of this continent pay a terrible price," Annan said, citing trouble in Congo and Angola, where he said the U.N.-brokered peace process is "hanging by a thread."

The Nonaligned summit is seen as a major opportunity to negotiate peace in the war between Kabila and the rebels, which has drawn troops from Angola, Zimbabwe and Namibia to Kabila's side.

Kabila, whose forces hold the upper hand, has refused to talk peace with the rebels. But his presence at the summit raised hopes of progress.

"It is good that (Kabila) is here," said Zimbabwe's envoy Danson Mudekunye. "The prospects for the peace talks are much better now."

Mandela and his new wife Graca Machel - widow of Mozambican president and black liberation leader Samora Machel - greeted the heads of state Wednesday. The South African president exchanged a particularly warm hug with Cuban President Fidel Castro.

"Fidel, Fidel, Fidel," Mandela said as he threw his arms around Castro.

Mandela, the new chairman of the Nonaligned Movement, addressed the summit and called on Western countries to reduce the debt burden of developing nations. He also said leaders of developing countries should refrain from abusing their power.