Rebel leaders and the Congolese government they are trying to unseat reached a breakthrough in peace talks yesterday, said President Frederick Chiluba of Zambia, chairman of the peace summit.
Mr Chiluba refused to give details and would not comment on whether a ceasefire had been reached, but said there was an agreement.
"All of us have agreed," he said. "Details of the agreement will be released tomorrow."
Meanwhile an Angolan warplane attacked the rebel-held town of Kalemie in the south-east of the Democratic Republic of Congo yesterday, killing 25 people and wounding 40 others, a rebel officer, Mr Jonas Taturu, told journalists.
President Chiluba said the group of regional presidents will reconvene this morning for further deliberations before issuing further information.
"We have had a very good meeting. Please take it things have gone extremely well," he told reporters.
The Congolese President, Mr Laurent Kabila, has refused to meet face-to-face with the rebels who control a quarter of his vast mineral-rich central African nation.
The rebels, excluded from two previous summits over the past month, arrived yesterday for talks with Mr Kabila, and the presidents of Angola, Zimbabwe, Namibia, Uganda and Rwanda.
Mr Kabila accuses Uganda and Rwanda of sending troops to back the rebels - a claim they deny - while Zimbabwe, Angola and Namibia have sent military help to back Mr Kabila's government.
"We are ready to talk, and we hope the leaders will listen to us," Mr Arthur Zahidi Ngoma of the rebel Congolese Democratic Coalition said at the airport. "There will be no ceasefire before political negotiations and no ceasefire before troops from Zimbabwe, Angola and Namibia leave."
A Congolese military official, Mr Francois Olenga, said Mr Kabila's delegation will resist attempts to persuade them to meet with the rebels. "They are not rebels. They are invaders," he said.