A United Nations aid convoy has reached one of the major rebel-held towns in the far east of the Democratic Republic of the Congo (DRC), providing urgent supplies to civilians trapped amid the fighting in the region, as United Nations officials led by Secretary-General Ban Ki-moon continue efforts to broker a solution to the conflict.

Mr. Ban told reporters today that he has appointed Olusegun Obasanjo, the former Nigerian president, to serve as his Special Envoy on the issue and to work with leaders in the region and the broader international community to end the crisis.

?The conflict along the Rwandan and Congolese border has gone on too long, with catastrophic consequences,? Mr. Ban said. ?We need peace ? an end to fighting so that the region's people can enjoy a measure of stability and prosperity.?

The Secretary-General also said he is willing to travel anywhere to meet DRC President Joseph Kabila and Paul Kagame, leader of neighbouring Rwanda, later this week for talks aimed at defusing ethnic tensions in the eastern DRC, a region that has remained highly volatile since the official end of the Congolese civil war early this decade.

?Though they have not yet sat down face-to-face, Presidents Kagame and Kabila have begun a direct dialogue, along with their high-level technical teams. This is a promising development,? said Mr. Ban, who has spoken by telephone with both leaders and dozens of other senior officials in recent days, emphasizing that there can be no military solution.

?I understand that the AU [African Union] President will also convene an urgent regional summit on this issue, in Nairobi or elsewhere in Africa, sometime soon this month.?

Deadly fighting in recent months across North Kivu province has forced an estimated 250,000 people to flee their homes, joining hundreds of thousands of other internally displaced persons (IDPs) across the region, and the clashes have even threatened Goma, the provincial capital and home to about 700,000 people.

The UN aid convoy that reached Rutshuru, a town in North Kivu, carried first aid and basic medicines for local health-care centres as well as equipment to re-establish clean water supplies, the UN Office for the Coordination of Humanitarian Affairs (OCHA) reported.

Blue helmets serving with the UN peacekeeping mission to the DRC (known as MONUC) escorted the convoy from Goma to Rutshuru, which is now held by the rebel National Congress for the Defence of the People (CNDP), headed by former Congolese army general Laurent Nkunda.

The UN World Food Programme (WFP) reports that IDP camps visited by its staff in Rutshuru were almost deserted, with many shelters burned to the ground. Some camp residents are believed to have returned to their home villages, but the agency said it is unclear where all the other residents have gone.

OCHA said ?armed actors? have been circulating at two other UN camps for IDPs, each located about 10 kilometres north of Goma and now largely deserted because of panic among the residents.

As IDPs have returned to camps around Goma, UN agencies and non-governmental organizations (NGOs) have been provided high-energy biscuits, water and medical supplies. But concerns remain high about the risk of infectious disease outbreaks, with 70 cases of cholera already recorded in camps, with the rainy season approaching.

WFP's operations in nearby Uganda have also started pre-positioning 500 tons of food ? enough to feed an estimated 30,000 people for a month ? at key locations in case Congolese escaping the violence decide to travel that way. A similar process is taking place at the Nkamira transit centre in Gisenyi, which is just inside Rwanda.

Meanwhile, Mr. Ban has reinstated a former Force Commander of MONUC, Lieutenant General Babacar Gaye of Senegal, as the new Interim Force Commander for the next six months after the recent resignation of Lt. Gen. Vicente Diaz de Villegas y Herrerķa of Spain for personal reasons.

?I wish to express my gratitude to MONUC's peacekeepers for holding steadfast in Goma ? a thin blue line against chaos,? he said. ?I am doing my best to reinforce our peacekeepers and humanitarian teams, and I call on world leaders to support us in every way possible.?

Earlier, speaking to reporters in New York by videolink from the DRC, senior UN officials said MONUC was doing all it could given its limited numbers and resources, as well as the size and terrain of the area it had to cover. The mission has a total of about 17,000 blue helmets, including some 5,500 spread across North Kivu.

Under-Secretary-General for Peacekeeping Operations Alain Le Roy, who is in the region to assess the situation, said it was ?clearly a huge humanitarian crisis? and noted that fighting had now broken out on four fronts in the eastern DRC.

Alan Doss, the head of MONUC, told reporters that the city of Goma is now calm as MONUC troops conduct regular patrols and a curfew is enforced. Looting has stopped and the mission's forces are working closely with Congolese police to maintain law and order.

He said the situation was being made more complicated by the presence of so many separate armed groups in North Kivu ? as many as 10 or 15 by some counts.

Ross Mountain, the Secretary-General's Deputy Special Representative in the DRC, said the protection of IDPs and other civilians is the biggest humanitarian priority, and warned that the ceasefire struck last week remains extremely fragile.

?Goma could be asphyxiated if the food supplies from the hinterlands cannot come into the city,? he said, emphasizing the importance of providing shelter, clean water and nutrition.