A statement from the summit in Nigeria said the Guinea-Bissau rebel leader, Ansumane Mane, and President Joao Bernardo Vieira failed to reach a final accord although they had agreed to try to consolidate a ceasefire and deploy observers.

Negotiators from the 16-nation ECOWAS regional grouping are expected to continue talks with the warring parties in Abuja, where the summit was held.

Mr Vieira: Refusing to stand aside

Rebels from the former Portuguese colony insist that foreign forces supporting the beleaguered president, Joao Bernardo Vieira, must leave.

But the president wants a West African intervention force.

"Unfortunately it is looking like the Bissau issue will ultimately be decided on the battlefield. The president refuses all offers to step aside honourably," one official added.

Diplomats said he had repeatedly turned down offers to be flown out of the country for his own safety.

Guinea-Bissau has been torn apart by a rebellion which began four months ago, forcing hundreds of thousands to flee their homes.

Mr Vieira is practically a prisoner in the capital Bissau, where the bulk of the army revolted in June and joined forces with sacked army chief Ansumane Mane.

The president is protected in the capital by troops from neighbouring Senegal and Guinea.

Delegates had expected a ceasefire deal after Mr Vieira and Mr Mane arrived at the summit together following talks in Gambia.

Senegalese President Abdou Diouf, who has sent troops into Guinea-Bissau to support Vieira, said he wanted to see an overall political settlement to the problems of the region before he withdrew the soldiers.

Moratorium on import of light arms

Earlier, the leaders agreed to a regional peace-keeping structure to help prevent and contain future crises.

Delegates also adopted a three-year moratorium on the manufacture, exportation and importation of light arms into the region.

On Sierra Leone, they agreed to strengthen the West African intervention force Ecomog.

But they turned down a request by the Liberian leader for Ecomog forces there to be put under his command.

Other developments included the launch of a regional travellers cheque, aimed at easing trade in the region, as part of a drive towards regional economic integration.

South African President Nelson Mandela also made an appeal for greater co-operation between regional bodies in Africa.

It was the first time a leader from outside West Africa attended the Ecowas summit.