President Barack Obama on Thursday asked Speaker Nancy Pelosi (D-Calif.) to attach amendments to the fiscal 2010 Defense spending bill to increase the Army by 15,000 troops.

The troop increase carries a price tag of nearly $1 billion, but the administration’s amendments offset the costs by reallocating funds from lower-priority DOD contingency operations, Obama says in a letter to the Speaker. The Defense bill passed the House last month but awaits Senate action — and, likely, a subsequent conference committee .

“Expanding the Army to 562,400 troops in 2010 will reduce stress and strain on soldiers and families,— said Obama. “I am committed to supporting our troops and will continue to promote policies that maintain their high level of readiness and that improve the quality of life of servicemembers and their families.—

The additional 15,000 troops are part of an overall increase of 22,000 Army troops that Defense Secretary Robert Gates says is needed over the next three years. Gates has said DOD funds can be reshuffled for fiscal 2010 and 2011 to pay for the troop increases, but he has not said how funds would be allocated beyond then.

Obama is on thin ice with anti-war Democrats in the House, who say they have given the president all the money he can expect to get for the wars in Iraq and Afghanistan, unless he can demonstrate progress toward ending the conflicts.

House Appropriations Chairman David Obey (D-Wis.), a vocal critic of the wars, last month refused to answer questions about whether he would be willing to sign off on more money for troops.