In the biggest attack, one soldier from Task Force Iron Horse was killed and four were wounded in a roadside bombing in Baqouba, 35 miles northeast of Baghdad. One of the wounded was critically injured and the other three were in guarded condition, the military said.

A soldier from Task Force Olympia was killed and another wounded by a bomb Monday evening in Tall Afar in northern Iraq. A soldier from the 1st Armored Division died and another was wounded in a bombing Monday in central Baghdad.

The latest deaths brought to 541 the number of Americans who have died since President Bush launched the Iraq war March 20. Most of the casualties have occurred since Bush declared an end to active combat May 1.

Witnesses said two roadside bombs exploded Tuesday outside the Anbar Medical College and hospital in Ramadi in the Sunni Triangle, damaging a US Army Humvee. It was unclear if any soldiers or civilians were injured. A third bomb was defused.

As the casualties mount, the United States and its allies are preparing to hand over sovereignty to the Iraqis by July 1, despite disagreements over the best way to choose a new government.

Some members of the Governing Council said the US-favored use of caucuses was losing support.

"This system is alien to us," said Naseer Kamel al-Chaderchi, a Sunni Muslim. "It's based on city councils and the integrity of these councils is in question."

He added that the Governing Council, which is sticking to the June 30 deadline for the transfer of power, hasn't had a formal discussion about caucuses, but said there is an "inclination" toward rejecting them.

Mahmoud Othman, a Kurdish Sunni member of the council, Agreed that the caucus plan has little support. He said the Americans could simply hand over sovereignty to the Governing Council but most Iraqis wouldn't accept it because the body was appointed by the United States.

"So the second option is to hold a national conference with the wide participation of political and religious figures. A leadership will emerge from this conference to take over," he said. "Personally I prefer the second option because I think it will enjoy the greatest support among Iraqis. They Americans are saying now that they will not block any option agreed upon by the Iraqi people."

On Monday, U.S. administrator L. Paul Bremer said he would move to block any effort by Iraqi leaders to put Islamic law as the foundation of legislation in the interim constitution, which is supposed to take effect at the end of February.

However, Mohsen Abdel-Hamid, the current president of the Iraqi Governing Council and a Sunni Muslim hard-liner, has proposed making Islamic law the "principal basis" of legislation, which many Iraqi women's groups fear will threaten their legal rights.