The United States Wednesday called for U.N. sanctions on Arab militias in western Sudan (search) whose attacks have sparked a humanitarian crisis and indicated it may seek penalties against Sudan's government if it doesn't stop the conflict.

A U.S. draft resolution would require the Security Council (search) to decide after 30 days whether an arms embargo and travel ban against the militias should be extended "to any other individuals or groups responsible for the commission of atrocities in Darfur."

The United States and humanitarian groups accuse the government of backing the militias, known as the Janjaweed (search), during the 15-month conflict that has killed up to 30,000 people, forced over one million to flee their homes, and left 2.2 million in desperate need of food and medicine.

The fighting began when two groups drawn from Darfur's African tribes took up arms in February 2003 over what they regard as unjust treatment by the government in their struggle over land and resources with Arab countrymen. Some human rights groups have accused the Janjaweed of ethnic cleansing and genocide (search).

But a resolution even hinting at sanctions against Sudan — which denies backing the Janjaweed — could face opposition from Arab and Islamic countries on the Security Council.

The Sudanese government signed a cease-fire agreement April 8 and the U.S. draft urges that it be implemented "without delay." The agreement calls for negotiations to end the conflict, disarming the militia raiders who have razed hundreds of villages, and lifting restrictions on access for relief workers.

U.N. Secretary-General Kofi Annan and Secretary of State Colin Powell teamed up in the Sudanese capital, Khartoum, on Wednesday to pressure the government to fulfill these promises.

Philippines U.N. Ambassador Lauro Baja, the current Security Council president, said the release of the U.S. draft was clearly timed to the high-powered visit. He said the resolution should send "a strong signal to the government" that it needs to take action.

In Washington, State Department spokesman Adam Ereli said the resolution was "part of a tapestry of diplomatic action" to get the Sudan to fulfill its commitments.

The U.S. draft would authorize an arms embargo and a ban on military training for the Janjaweed. It would also impose a travel ban on Janjaweed militia members whose names are on a list that would be compiled by a new Security Council committee that would monitor the sanctions.

The proposed resolution also calls on the Sudanese government "to cease all military attacks in Darfur, disarm and neutralize the Janjaweed militias ... protect civilians ... cooperate fully with all humanitarian relief organizations and provide them unrestricted and sustained access for the provision of humanitarian relief."