Updated

A group of U.S. senators met Tuesday with Iraq's interim prime minister to discuss the formation of a national unity government, a step viewed as important in working toward peace and a withdrawal of U.S. troops.

Interim Prime Minister Ibrahim al-Jaafari said he believed Iraq's most difficult political hurdles had been crossed and predicted a new government would be ready in the coming weeks.

"I hope that the formation of the new government does not last beyond April," al-Jaafari said.

Sen. Carl Levin of Michigan, ranking Democrat on the Senate Armed Services Committee, cautioned al-Jaafari about the importance of adhering to such a commitment.

"April is fine, but it is necessary that this commitment be kept in order for there to be continued support for the presence of American troops in Iraq," he said. "There's got to be some pressure put on leaders of this country to reach a political settlement."

The committee chairman, Sen. John Warner, R-Va., said decisions on U.S. troops would be made not only by President Bush, Congress and other leaders, but also by the American people — an apparent allusion to declining U.S. popular support for the war.

"If it's perceived in America that they are proceeding with this government in less than a sincere and prompt way, then the people of the United States of America will speak up and speak up very loudly," Warner said he told al-Jaafari.

Iraqi leaders still have not formed a government more than three months after landmark elections for the first permanent post-invasion parliament.

They announced agreement on setting up a Security Council to deal with key matters while negotiations proceed. The announcement came Sunday after the fourth in a series of U.S.-brokered all-party meetings on forming a government.

"It was a successful meeting, and we have agreed on forming a National Security Council whose powers will not contradict the constitution," said Adnan al-Dulaimi, a Sunni Arab political leader.

The council, to be headed by President Jalal Talabani, was established as an interim measure as politicians struggle to agree on the makeup of a government following the Dec. 15 parliamentary elections.