Updated

In a grim report on the 20-month conflict in Sudan's Darfur (search) region, Secretary-General Kofi Annan (search) says violence intensified in October and there are strong indications of war crimes "on a large and systematic scale."

He accused the government and rebels of trying to take more territory in Darfur instead of complying with U.N. demands to end the violence, disarm government-backed Arab militias blamed for many attacks and punish the perpetrators.

Jan Pronk, the top U.N. envoy to Sudan who wrote the report, will present it to the Security Council on Thursday. It recommends that members take "prompt action" to get the government and rebels to comply with the U.N. resolutions and urges countries with influence to exert pressure on the parties to negotiate a peace deal.

The United Nations (search) has called Darfur the world's worst humanitarian crisis, saying the conflict there has claimed 70,000 lives since March — mostly through disease and hunger.

Originally a clash between black African farmers and Arab nomads over the distribution of scarce resources, the conflict has grown into a counterinsurgency in which pro-government Arab militia have raped, killed and burned the villages of their enemy.

According to the report circulated Wednesday, the estimate of people affected by the conflict rose during September from 1.8 million to 2 million and is expected to continue climbing in the months to come.

The increase stems mainly from the growing number of people who have fled their homes, now 1.6 million, the report said. A further 400,000 people are in need of humanitarian assistance.

Pronk said the 2 million figure is a 100 percent increase in the number of people needing humanitarian assistance since April. Donors have funded 75 percent of the money needed for Darfur this year — $397 million of $534 million. He appealed for the rest.

The report also cited various sources as saying a new rebel group that calls itself the National Movement for Reformation and Development has attacked government troops and threatened a small African contingent seeking to stabilize the area.

Until the government starts taking more than "pinprick" action against the perpetrators, the report warned, no displaced person will dare return home and no group will agree to disarm.

"Without an end to impunity ... banditry goes from strength to strength, menacing the population and obstructing the delivery of aid to desperate people in isolated areas," it said.

The report cited the abduction and alleged rape of seven women in West Darfur, the massacre of at least 14 civilians in a market in South Darfur and an attack by armed men on horseback who killed four civilians and looted cattle in a village in North Darfur.

"Neither side is refraining from conducting attacks against the other or exercising restraint when attacked," the report said.

The report accused the Sudanese government of failing to bring the perpetrators of widespread killings, rapes, looting and village burnings to justice.

An international commission appointed by Annan began work on Oct. 25 and has three months to study human rights violations and determine whether or not a genocide occurred in Darfur.

"There are strong indications that war crimes and crimes against humanity have occurred in Darfur on a large and systematic scale," the report said. "This has been confirmed by a number of senior U.N. human rights experts who have visited the region."

There have been reports that armed men dug up a grave containing 40 bodies in Souba, North Darfur and have been seen working on another site in an apparent attempt to hide evidence of mass killings, it said.

The report called for stepping up efforts to end the conflict in Darfur and another 21-year civil war between the government and rebels in southern Sudan.

The Security Council will be holding a rare meeting in Nairobi, Kenya, where talks to end the civil war are taking place, on Nov. 18-19. The talks are proceeding well and a final agreement can be reached by the end of the year and "serve as a model for Darfur," the report said.

U.S. Ambassador John Danforth said Wednesday the council trip aims to show the Sudanese what the country would look like if there were peace — including international guarantees of a peace agreement, international monitoring, and development assistance.

But he warned that this "carrot" — the offer of international help — won't "be there forever" and "if we are pushed away by either side" then the international community will turn to other pressing global issues.