"I hate to throw out numbers, but I have seen numbers that will approach the enlisted category perhaps as high as the mid-20s -- 23, 24,000," Thomas R. Lamont, the Army's top personnel official, told the Senate Armed Services Committee's personnel subcommittee Wednesday.
"And on the officer contingent -- again these are very rough numbers and all based again on assumptions and attrition rates -- officers may go up to 4,500, maybe 5,000," said Lamont, assistant Army secretary for manpower and reserve affairs.
"There will be some officers -- and there will be some very good non-commissioned officers -- that will want to stay in the Army and will probably not," added Lt. Gen. Thomas P. Bostick, Army deputy chief of staff.
Lamont and Bostick were among military officials testifying a day before House Armed Services Committee panels were to begin marking up the fiscal 2013 National Defense Authorization Bill.
The Republican-controlled committee has said it intends to add about $8 billion to the $546 billion for defense set by the Budget Control Act that ended last year's U.S. debt-ceiling crisis.
The crisis threatened to push the federal government into sovereign default on or about Aug. 3, 2011.
The act will trigger across-the-board spending cuts of more than $100 billion a year, starting next fiscal year, if Congress doesn't identify ways of cutting the deficit at least $1.2 trillion during the next decade.
Those reductions -- split evenly between defense and non-defense programs -- would hit the Pentagon with a $54 billion cut in 2013.
The Obama administration seeks to cut defense spending in fiscal 2013, but increase it afterward, just not as fast as previously planned.
The House GOP plan calls for defense spending to be at the same rate next year as it is this year, and future increases to be higher than the White House plan.
Defense Secretary Leon Panetta said Jan. 26 that under the 2013 defense budget, the Army would lose 80,000 soldiers as the Army shrinks to 490,000 from a 570,000 peak, but he did not say then whether the reduction would be through layoffs or through attrition as soldiers retire.
Panetta said the number of Marines would drop by 20,000 to 182,000, the Air Force would buy fewer new Lockheed Martin F-35 Lightning II jet fighters and scrap 92 cargo planes and jets, and the Navy would lose seven cruisers.
Pay raises would be limited beginning in 2015, and healthcare fees for retirees would rise, Panetta said, adding the moves would not compromise security.
Funding for special operations forces trained to perform high-risk dangerous missions, such as the raid that killed Osama bin Laden, would continue to grow as would the military's fleet of drones, Panetta said.
The troop reductions "are potentially devastating to our national security," Senate Armed Services Committee member Joseph Lieberman, Ind-Conn., said after Panetta presented his proposed "tough budget choices" needed to reach $487 billion in cuts over 10 years.
These reductions, which would require congressional approval, "are the result of budget pressure, not what is best for America's security," Lieberman said.
House Armed Services Committee Chairman Howard McKeon, R-Calif., said Wednesday he would seek to increase funding for new M1 Abrams battle tanks, guided-missile Navy destroyers and a mobile air defense system in the defense budget, and seek to put a brake to the planned reduction in military force numbers.