WASHINGTON (AP) – The Army is considering whether it would have to extend the combat tours of troops in Iraq if President Bush opts to maintain a recent build up of forces through spring 2008.

Acting Army Secretary Pete Geren testified Tuesday that the service is reviewing other options, including relying more heavily on Army reservists or Navy and Air Force personnel, so as not to put more pressure on an already thinly stretched active-duty force.

Most soldiers spend 15 months in combat with a guaranteed 12 months home, a rotation plan that already has infuriated Democrats because it exceeds the service’s goal of giving troops equal time home as in combat. In coming weeks, the Senate will vote on a proposal by Senator Webb, Democrat of Virginia, that would restrict deployments.

“It’s too early to look into the next year, but for the Army we have to begin to plan,” Mr. Geren told the Senate Armed Services Committee. “We have to look into our options.”

General David Petraeus, Iraq war commander, on Sunday suggested that conditions on the ground might not be stable enough by September to justify a drop in force levels and predicted that stabilizing Iraq could take as long as a decade. Earlier this year, Bush ordered the deployment of some 30,000 additional troops as part of a massive American-led security push around Baghdad and the western Anbar province.

When asked by Senator Levin whether maintaining the force build up would affect soldiers’ 15-month combat schedules, Mr. Geren said he was unsure and cited “numerous options” available, including using a “different utilization of the Guard and Reserve” and relying on the other services for help.

“We’re committed to filling the requirements that the combatant commander asks,” Mr, Geren said. “We have been able to do so up until now, and we will continue to do so.”

The Army assessment comes as Democrats say they are already frustrated with the existing policy.

“Who was talking for the well being and the health of the soldiers when this requirement was put down?” asked Mr, Webb, referring to the 15-month combat tours. After four years of combat, the strategy in Iraq cannot “justify doing this to the soldiers in the Army and the families back here,” he said.

Senator Lieberman, Independent of Connecticut, disagreed and said the Army should do more to add soldiers to its payroll.

“We never want to be in a position where our resources determine our strategy, instead of our resources being there to meet what our generals on the ground say they need to succeed,” Mr. Lieberman said.

Mr. Geren said the decision to extend tours from 12 to 15 months was made to ensure soldiers were guaranteed one year at home. Previously, soldiers deployed for 12-month cycles but were unsure when they would be sent back.

“I felt it was the best of the two tough choices to make. . . . That decision I believe was the right one,” Mr. Geren said.

The Senate panel is expected to approve Bush’s nomination of Geren as Army secretary, replacing Francis Harvey who was pushed out amid a scandal on deplorable conditions at Walter Reed Army Medical Center.