Jan Egeland warned Wednesday that the country could face a major humanitarian disaster within weeks unless there was a true cease-fire and a renewed effort to reach a lasting peace.

More than 200,000 people have been killed and 2.5 million displaced since rebels from ethnic African tribes rose up against Sudan's Arab-led central government. The Khartoum government is accused of retaliating with the janjaweed militias of Arab nomads, and violence has only increased since the government and one rebel group signed a peace agreement in May.

Government forces, militias, rebel groups, and an increasing number of opposition groups from neighboring Chad roam freely inside and outside refugee camps, "spreading fear and terror," Egeland said.

"Villages, camps and communities outside the urban centers of Darfur are again being burned and looted," he said. "Women and children are raped and killed with impunity."

Egeland said the situation in Darfur is "closer to the abyss than I have witnessed since my first visit in 2004."

The number of people in need of aid increased to 2 million in 2005, 3 million this spring, "and now there are 4 million in desperate need of humanitarian assistance — and that in a climate of massive rearmament," he said.

He blamed the Sudanese government, the Arab militias and rebel groups for fueling the conflict — and the international community for not protecting innocent civilians living in fear of rape and killings, as world leaders pledged to do at a U.N. summit in September 2005.

Egeland just completed his fourth and final mission to Darfur. He steps down as the U.N. undersecretary-general for humanitarian affairs and emergency relief coordinator next month.

In a report to the

U.N. Security Council and comments to reporters afterward, he said the best hope for peace is an agreement last week between Sudan and the

United Nations that could open the door to the deployment of thousands of U.N. troops in Darfur as part of a "hybrid" U.N.-African Union force.

The agreement also called for a revitalized effort under U.N. and AU auspices to persuade more rebel groups to sign the Darfur Peace Agreement.

Secretary-General

Kofi Annan, briefing the council later, said the AU and the U.N. would soon call a meeting of groups that have refused to sign the peace agreement "with the hope of resolving outstanding issues by the end of the year."

If there is "massive pressure on the parties" from all 15 members of the Security Council, and from Asian, African and Islamic countries, Egeland said, "we may make historic deals on the political front."

Annan has called for a force of 17,000 soldiers and 3,000 police officers for Darfur. The AU has 7,000 peacekeepers in the region, which is the size of France.

Annan told reporters that he had spoken Wednesday to Sudan's President Omar al-Bashir, who indicated "he will be writing to me shortly." Al-Bashir vehemently opposed the transfer of peacekeeping in Darfur from the AU to the United Nations.

Egeland said that the crisis could largely stop with a cease-fire, a peace agreement and deployment of a peacekeeping force that protects civilians.

"This can all change if there is a change in will," he said. "It has to happen in Sudan, and it has to happen internationally."