UNITED NATIONS – The U.N. secretary-general, Kofi Annan, said yesterday that Sudan’s government has not stopped attacks on “terrorized and traumatized” civilians in its Darfur region and urged the speedy deployment of an expanded international peacekeeping force.

Mr. Annan did not say how large a force he wanted, but U.N. diplomats said a U.N. plan presented to the African Union called for about 3,000 peacekeepers. The 53-nation African organization now has about 80 military observers in Darfur, protected by just over 300 soldiers, monitoring a rarely observed cease-fire signed in April.

Mr. Annan’s report was called for in a Security Council resolution that was adopted July 30 giving Sudan 30 days to demonstrate it was curbing nomadic Arab tribes accused of killing thousands in attacks on African farm villages and also improving access for aid groups. The resolution threatened punitive economic and diplomatic measures if Sudan didn’t move quickly.

The secretary-general didn’t mention or recommend sanctions, which many council members oppose at this point. His call for an expanded international force, by contrast, was likely to get strong support, especially from America.

The 15 Security Council members are to be briefed today by Mr. Annan’s top envoy to Sudan, Jan Pronk, whose observations form the basis of the report’s conclusions and recommendations.

The report criticized the Sudanese government for failing to meet its key obligations under agreements with the United Nations to rein in the Arab rebels, which are accused of killing up to 30,000 people and forcing 1.5 million to flee their homes in the vast and arid Darfur region.

Stemming from long-standing disputes over scarce water and arable land, the conflict erupted when two African groups rebelled last year accusing Sudan’s Arab-dominated government of siding with the Arab herders. Aid groups have accused the government of encouraging and supporting the attacks, a charge Sudanese leaders deny.

“The most critical commitment that has yet to be implemented relates to the armed militias which continue to pose a serious threat to the civilian population,” Mr. Annan’s report said. “Attacks against civilians are continuing and the vast majority of armed militias has not been disarmed.”

On the positive side, Mr. Annan cited “some progress” by the government in improving security in newly designated havens for refugees, the deployment of additional police, the beginning of disarmament, and the lifting of restrictions to aid shipments.

He also noted the government kept its promise to resume peace talks with the rebels. But his report made clear much more needed to be done.

“The displaced have been terrorized and traumatized, and have lost confidence in the authorities,” Mr. Annan said.