By Haider Haidoura
ALGIERS, April 30 (Reuters) - Six African leaders wrapped up a one-day summit on the Democratic Republic of Congo conflict on Sunday and called on the U.N to speed up deployment of a 5,500-strong peacekeeping force.

They said in a three-page statement that Africa's regional powers Nigeria and South Africa had pledged to contribute forces to peacekeeping in the continent's third biggest country..

"The heads of state urged the (United Nations) Security Council to speedily implement Phase II of the deployment of U.N. forces, so as to consolidate the progress made so far," the statement said.

The meeting, chaired by Algerian President Abdelaziz Bouteflika, chairman of the Organisation of the African Unity (OAU), was attended by President Laurent Kabila and the presidents of Nigeria, South Africa, Mozambique and Mali.

Algerian officials earlier said Zambian President Frederick Chiluba was due to take part but he did not show up and sent a minister instead.

"The heads of state welcomed the offer made by the Republic of South Africa and Federal Republic of Nigeria to place troops at the disposal of the U.N. force in the Democratic Republic of Congo," they said.

They also urged the parties involved in the Congo war to respect a ceasefire and a peace accord reached last year in the Zambian capital Lusaka.

"They reaffirmed the importance and validity of the Lusaka agreement which constitutes an irreplaceable framework for the resolution of the conflict. They called upon the parties to scrupulously honour their commitment so as to consolidate the ceasefire," the statement added.

Six African nations fighting in Congo signed the Lusaka peace deal last year, but clashes have continued.

Uganda and Rwanda are supporting rebels fighting to oust Kabila, whose army in turn is backed by Zimbabwe, Angola and Namibia.

At a meeting in Uganda at the beginning of April, the warring parties reaffirmed the ceasefire deal, and a new truce took effect on April 14.

The U.N. Security Council has approved a 5,500-strong force to monitor the peace process, but has yet to deploy it, prompting Kabila to accuse the U.N of dragging its feet.

The six leaders, who dubbed their summit "an additional step in the collective and continuous efforts of Africa to resolve the crisis in the Democratic Republic of the Congo", called on the Congolese factions to engage in dialogue towards restoring peace.