"The situation in Darfur is very critical," said Sally Chin of Refugees International, a Washington, D.C.-based humanitarian group, who recently returned from Sudan, where she spent two months preparing a new report based on interviews with scores of officials and civilians.

The report, titled "No Power to Protect," argues that the African Union Mission in Sudan, also known as AMIS, will not be effective in preventing bloodshed unless the U.N. and the U.S. take active steps to provide additional support.

"The African Union has been given the responsibility to protect, not the powers to protect," Chin noted in a conference call with the media Wednesday. "The people of Darfur are in serious jeopardy. This force is their last hope, and in its current state, it's not capable of delivering."

The African Union troops were deployed in the region after the U.N. Security Council adopted a unanimous resolution that authorized AMIS only to monitor the ceasefire agreed in early 2004, as well as to assist in confidence-building measures between the warring parties.

According to Refugees International, the fact that AMIS has no mandate to protect civilians is emboldening the Janjaweed militia, who are widely believed to operate with the support and approval of the Sudanese government, to continue attacking civilians.

The report argues that limited resources and a strict mandate is crippling the AU force's ability to protect civilians facing fresh wave of abductions and killings by the Janjaweed.

A strict interpretation of its mandate does not allow AMIS to protect civilians from imminent attack unless the AMIS troops are present at that very moment.

"Even when AMIS knows an attack is coming, it is unable to react," said Chin, adding that the AMIS force itself is so weak that militia fighters are not afraid to attack it directly.

"The AU mission is outgunned by the government of Sudan and the armed factions," explained Jonathan Morgenstein, a consultant for Refugees International and co-author of the report, also on Wednesday's call with reporters. "The Sudanese army and militias have heavy weapons, whereas AMIS have only AK-47 rifles."

Currently, the AU is depending on 5,000 troops, which Morgenstein and others think is not a large enough force to deal with the threat of violence being posed by the militia. "I think 12,500 is doable," Morgenstein said.

Voicing its concern over the Darfur situation, New York-based Human Rights Watch has also called for the expansion of AU troops.

"There is an urgent need for the international community to do more to protect civilians from further violence," said Human Rights Watch's executive director for the Africa region Peter Takirambudde in a recent statement, noting that the security situation in Darfur has deteriorated in the past two months.

"Additional troops and equipment and a more aggressive interpretation of the mission's mandate are required if civilians are to be adequately protected."

According to Refugees International, in the past two months the Janjaweed have not only attacked the villages, but also the camps, where internally displaced people of Darfur are taking refuge from violence.

Over the past two years, as many as 400,000 people of Darfur have been killed and over two million have been displaced as either refugees in neighboring Chad or internally displaced persons in camps across Darfur.

Critical of the U.S. role in addressing the Darfur conflict, both Human Rights Watch and Refugees International have questioned why Washington cut $50 million from the Foreign Operation Spending Bill that it had pledged for AMIS.

"Along with the European Union, and other donors, the U.S. should ensure that the funding needs of the existing operation and any other expansion of AMIS are met," Takirambudde said last week in a letter to Deputy Secretary of State Robert Zoellick.

Noting that top U.S. officials had called the Darfur situation "genocide," Refugees International's Morgenstein wondered why the U.S. government is not willing to fulfill its pledge for financial assistance to AMIS.

"Congress should be ashamed of itself," he said. "It's cold, passive negligence."

Noting political sensitivities over the potential transfer of peacekeeping duties to the United Nations, Refugees International suggested that the U.S. must lead the discussion on this issue "as soon as possible."

"This is especially necessary because the Sudanese government is slated to become the next chair of the African Union in January," explained Chin. "The prospects for peace increasingly look dim."

Noting that Zoellick is currently visiting Sudan, the group said it's not sure whether rebel groups or the Sudanese government will be eager to respect the ceasefire.