WASHINGTON — Sen. Sheldon Whitehouse said Wednesday that his talks with U.S. military and diplomatic leaders in Iraq last week have left him optimistic that, while tens of thousands of American troops must remain in Iraq for an indefinite period of time, the U.S. combat force can safely be removed from Iraqi municipalities by summer and from the rest of the war-torn nation by three years from now.

Those withdrawal timelines from a new U.S.-Iraqi agreement are both “shorter and longer” than the timeline in President-elect Obama’s campaign pledge to remove the combat force from Iraq within 16 months after he is inaugurated, Whitehouse said on the telephone from Dubai. Barring unforeseen problems, Whitehouse said, the military situation in Iraq is such that the bulk of the American force of more than 140,000 can be removed in accordance with the terms of the “Status of Forces Agreement” recently adopted by the two nations.

Many challenges remain, Whitehouse said, but Iraq’s armed forces have improved to the point where they can rapidly assume the combat duties of the departing Americans. Nevertheless, a substantial U.S. force must remain for an uncertain period of time to provide the Iraqis with such services as intelligence, air support, transportation and other logistical help, said the Rhode Island senator.

Whitehouse, a member of the Senate Intelligence Committee, spoke near the close of a weeklong journey that took him and fellow senators to Egypt, Jordan, Iraq and Dubai. The Senate delegation was led by Sen. Byron Dorgan, D-North Dakota. In Iraq, they met with such officials as Army Gen. Raymond T. Odierno, commander of the U.S. forces there, and U.S. Ambassador Ryan C. Crocker

Whitehouse said Crocker is “quite optimistic” provincial elections scheduled for early next year will be a step toward fuller representation of all of Iraq’s competing ethnic and religious groups, especially the Sunni Muslim minority that boycotted earlier elections and gave much support to the violent insurgency that has now been largely quelled. “This means the Sunnis will have a better forum to work out their differences” with the Shiite majority, Whitehouse said.

He said U.S. officials reported there is great enthusiasm about the coming elections, with many candidates running from all quarters in campaigns focused heavily on pledges to fight corruption and deliver services to the people — issues, in other words, that would be familiar to American voters.

Whitehouse called his travels to the other three countries “interesting and educational.” He said he heard a common theme in talks with the three heads of state, President Hosni Mubarek of Egypt, King Abdullah II of Jordan and Sheikh Mohammed of Dubai. All three leaders sought to assure the senators of their strong feelings of friendship with the United States, their dissatisfaction with President Bush’s policies in their region and their high hopes for better things from President-elect Obama.

If anything, Whitehouse said, hopes and expectations for President Obama’s administration are even higher in the Muslim world than in the United States. That could carry the danger that expectations are too high for Obama to meet, he said. But he termed that “a high-quality problem” to be dealing with in the Middle East.

jmulligan@belo-dc.com