Congress' two Muslim members urged the U.S. government on Wednesday to lead efforts to end the violence in Sudan's Darfur region, where more than 200,000 people have died and 2.5 million have been displaced.

Reps. Keith Ellison of Minnesota and Andre Carson of Indiana joined other black Democratic lawmakers making that call at a "Muslim Voices for Darfur" news conference on Capitol Hill Wednesday. Sudan is a predominantly Muslim African nation.

Ellison, a freshman lawmaker, asked Sudan's government to stop the violence.

"I further call on Secretary of State Condoleezza Rice to exert all available influence on the international community and on the parties to the conflict," he said, "and I especially urge Secretary Rice to engage allies among majority-Muslim nations and the African Union."

Ellison was elected as the nation's first Muslim member of Congress in 2006, and Carson became the second after winning a special election this year to fill the remainder of his late grandmother's term.

"We talk about America being one of the greatest nations on earth," Carson said. "If we are to have that title _ it's arguable _ we need to step out on the world front and be a leader on this issue."

Fighting has raged in Darfur since 2003, when ethnic African tribesman took up arms, complaining of decades of neglect and discrimination by the Sudanese Arab-dominated government. The Sudanese government is accused of unleashing janjaweed militia forces to commit atrocities against ethnic African communities in the fight with rebel groups. The Sudanese government in Khartoum denies the accusations. President Bush has labeled the situation there genocide.

The most direct challenge to the Bush administration came from Rep. Sheila Jackson Lee, D-Texas.

"It's time for Secretary Rice to make a singular mission to Africa on the genocide in Sudan," she said. "... and not come back until troops are on the ground, until the African Union is reinforced, until the Khartoum government is aware of our seriousness that the genocide must stop."

A joint U.N.-African Union force, which took over peacekeeping duties in Darfur in January from a beleaguered AU force, has only about 7,500 troops and fewer than 2,000 police on the ground, out of a total of 26,000 that have been authorized.

"We've been deeply concerned that the deployment of the troops is not moving quickly enough, and we continue to press to make that happen," State Department spokesman Bill Strassberger said in a telephone interview. "We need to stop the violence that's resulting in deaths of innocent civilians, and hindering the distribution of lifesaving humanitarian assistance to the areas of Darfur."

Other participants at the news conference said that Muslims around the world weren't doing their share.

"States that are making fantastic profits on oil today have not given one penny to Muslim brothers who are starving, who are being killed," said Rep. Donald Payne, D-N.J., chairman of the House Foreign Affairs Africa subcommittee.

Omer Ismail, a Darfur native, said that "one billion Muslims around the world are keeping silent on this issue ... We need to have new leadership in the Muslim world, we need to have new leadership in the Arab world."