Secretary-General Kofi Annan (search) raised the possibility Thursday of international intervention to protect more than 1 million people threatened by fighting in the Darfur region of western Sudan (search).

The Sudanese government is responsible for safeguarding civilians in Darfur (search), Annan said, but it may need help from the international community.

"And the Sudanese government should be willing to accept that assistance," Annan said.

Fighting between Arab militias, believed to be backed by the government, and the black African population has killed thousands of people and forced more than 1 million to flee their homes.

The Sudanese government has denied backing the militias, known as the Janjaweed, blaming the trouble in Darfur on rebels and criminal gangs.

Annan said he wasn't ready to describe the situation in Darfur "as genocide or ethnic cleansing yet" but he did call it "a tragic humanitarian situation."

Last week, the Security Council adopted a resolution giving the United Nations a green light to start planning for a U.N. peacekeeping mission in Sudan.

At the moment, the peacekeepers are supposed to monitor an agreement, expected to be finalized shortly, that will formally end a 21-year civil war in southern Sudan, but their mission could be expanded to Darfur with council agreement.

Annan told reporters he plans to visit Sudan "sometime soon" but didn't confirm a report in the country's al-Anbaa daily that he will travel to Darfur for a first-hand assessment of the conflict and the humanitarian crisis.

The United Nations has asked the Sudanese government "to take steps to contain the Janjaweed militia who are doing quite a lot of the killing and disruption of the lives of the people in the region," he said.

"They deny any complicity and indicated that they are going to do the best then can to bring the situation under control," Annan said. "I don't have specific evidence, but from all accounts they can do something about the Janjaweed."

Undersecretary-General for Humanitarian Affairs Jan Egeland had said that the number of people in acute need of food and medical help in Darfur has nearly doubled from 1.2 million to 2 million.

"We are rushing to get as much supplies on the ground before the rains come," Annan said Thursday. "We have also been putting pressure on the Sudanese government to allow humanitarian workers ... to be given free access to Darfur and allow supplies and equipment to come it. Things have improved but much more needs to be done."

Egeland on Monday called Darfur the worst humanitarian crisis in the world today and accused the Sudanese government of hindering efforts to get desperately needed food, water, sanitation equipment, tents and other supplies to the region before the rainy season.

"We've been working for many, many weeks in a race against the clock, and we see that the government, which should do its utmost to help us, is still not helping," Egeland said. "Some ministers are helping us, but some of their subordinates are sabotaging us."