The BBC's Ishbel Matheson: Severe setback to peace

The six governments involved in the Congo war signed the accord, but there are now grave doubts over whether the agreement can have any meaning without the support of the rebels.

"We didn't sign and we didn't commit ourselves," Moise Nyarugabo, Vice-President of the main rebel group, the Congolese Rally for Democracy (RCD), said from his headquarters in the eastern Congo.

"For us there is no agreement and there is no ceasefire."

President Laurent Kabila signed the accord, along with his allies Zimbabwe, Angola and Namibia, and the rebels' backers, Rwanda and Uganda.

The ceasefire plan was to have been the culmination of six weeks of negotiations intended to end an 11-month civil war.

Rebels divided

Ernest Wamba dia Wamba: Wanted to sign on behalf of RCD

But the ceremony was delayed when Ernest Wamba dia Wamba - recently ousted as RCD leader - insisted on being recognised as the RCD's signatory to the accord.

Emile Ilunga, the new RCD leader - who opposed the participation of Professor Wamba and his faction in the peace talks - said he would not put his signature alongside that of Professor Wamba.

The Movement for Congolese Liberation (MLC) - a separate rebel movement which has fought alongside the RCD - said it would sign only if both the RCD faction leaders also signed.

Hidden agendas?

In a sign of yet another internal division, the former spokesman for Prof Wamba's faction appealed to the international community not to heed Prof Wamba's insistence that he be allowed to sign.

Prince William Mishiki said that Prof Wamba's intransigence was part of an attempt by Uganda to retain political influence over the rebels, since the co-operation of the Ugandan-backed MLC is dependent on Prof Wamba signing the accord.

Other commentators have accused Rwanda of secretly backing the rebels' refusal to sign.

Kabila accused of bombing

Mr Bemba has told the BBC that a Sudanese Antonov bombed the rebel-held Balalita town in north-east Congo on Sunday morning.

Mr Bemba said that the bombing by the Antonov, which reportedly came from the direction of Bangui in the Central African Republic, proved that Congolese President Laurent Kabila was not serious about any ceasefire proposal.

Chiluba optimistic

Zambian President Frederick Chiluba, who chaired the talks, said he is still confident that the rebel groups will resolve their differences.

He also noted that without the foreign powers backing the rebels the chances of a peaceful settlement were much higher - an analysis shared by some diplomats in Lusaka.

But there are fears that covert backing to the rebels could prolong the war further.

The BBC's correspondent in Lusaka, Ishbel Matheson, says it remains more doubtful than ever whether peace can be delivered.

She says that if the presence of some of Africa's most powerful leaders in Lusaka could not persuade the rebels to sign, then it is unlikely that any other measure would prove successful.

The rebels have gained control of up to 50% of the country since beginning their insurgency against President Laurent Kabila in the east of the country last August.