An agreement on the rounding up and repatriation of Rwandan rebels from the Democratic Republic of Congo is to be extended by 90 days, says South African President Thabo Mbeki.

Following talks with Congolese President Joseph Kabila and his Rwandan counterpart, Paul Kagame, Mr Mbeki added that the UN Security Council would be asked to urgently review the mandate of the UN observer force in Congo.

The presidents were meeting in South Africa to review a peace accord signed in July, which saw Rwandan troops pull out of eastern Congo.

It is estimated that more than two million people have died, most from starvation and hunger, during the four years of war, which involved troops from several foreign countries.

Earlier, the signing of a preliminary power-sharing agreement between the Democratic Republic of Congo government and rebel forces was called off, with the rebels saying that vital parts of the deal had not been discussed.

The exact details of who would control which ministries in a national unity government under President Kabila was thought to be the main sticking point.

However, a spokesman for the presidency in South Africa said it was being delayed until 15 November as officials were busy with the meeting between the Congolese and Rwandan presidents.

Repatriation

Meanwhile, South Africa has defended its decision to repatriate eight Rwandan refugees from DR Congo on Wednesday.

Rwanda wants to stop infiltration by Hutu rebels

A Foreign Ministry spokesman in Pretoria, Ronnie Mamoepa, said the decision to return them to Rwanda was taken in conjunction with the United Nations.

However, the UN observer force in the Congo, Monuc, has denied being involved in the operation.

South Africa and Monuc are tasked with voluntarily repatriating Rwandan militias and soldiers from Congo.

The United Nations refugee agency, the UNHCR, has protested to the president of the Democratic Republic of Congo, Joseph Kabila, about the forced repatriation, saying the eight were members of an opposition political party. One is believed to be a senior leader.

Rwanda has consistently said it sent troops into eastern DR Congo to pretoct itself from Hutu rebels and former members of the Interahamwe who carried out the 1994 genocide.

Troops

On Thursday, a ceremony was held in DR Congo to bid farewell to the last troops from Angola, Zimbabwe and Namibia to leave the country.

Foreign contingents in DRC at height of war

Rwanda: 25,000 Zimbabwe: 12,000 Uganda: 10,000 Angola: 8,000 Namibia: 2,000

At the peak of their deployment, the three countries had more than 20,000 men in DR Congo fighting for the government against rebels backed by Uganda and Rwanda.

Rwanda withdrew the last of its troops from DR Congo earlier this month.

And Uganda has pulled out of almost all the areas it controlled in eastern Congo - except for a force asked to help keep the peace upon the request of the UN.

Warring militias in the east have been taking advantage of the power vacuum caused by the departure of foreign troops to intensify their activities.