In the meantime, the Pentagon will offer extra pay to soldiers who continue to serve under the policy, Gates said.
About 13,000 soldiers are serving under the stop-loss policy, nearly double the total of two years ago. Gates said the goal is to reduce that number by 50 percent by June 2010 and to bring it down to scores of soldiers by March 2011.
"I felt, particularly in these numbers, that it was breaking faith" to keep soldiers in the service after their end date comes up, Gates said. "To hold them against their will . . . is just not the right thing to do," he said at a Pentagon news conference.
The Army Reserve will no longer mobilize units under stop-loss policy beginning in August, the Army National Guard will follow suit in September, and the active-duty Army, by January. Currently, the Army has 1,452 Reserve soldiers, 4,458 National Guard troops and 7,000 active-duty soldiers on stop-loss.
Effective this month, the Army will also pay soldiers who are under stop-loss an extra $500 per month, and those payments will be retroactive to October, when they were authorized by Congress, Gates said.
Still, Gates said that changes "do carry some risk," and that the Army retains the authority to use stop-loss under "extraordinary" circumstances. But he said that should happen only in an "emergency situation where we absolutely had to have somebody's skills for a specific, limited period of time." Such decisions would be made by the secretary of the Army, he said.
Such a renewed use of stop-loss might stem from a sudden demand to deploy a large Army force, said Lt. Gen. Michael Rochelle, the Army's deputy chief of staff for personnel.
"Stop-loss has been a vital tool," Rochelle said. But, he added, "we know that this has been a hardship . . . on Army families."
Stop-loss began with an executive order in 1990, which gave the defense secretary the authority to hold on to or bring back from retirement military personnel deemed essential to U.S. national security. The Army used it during the 1990-1991 Persian Gulf War and again after the 2001 terrorist attacks.
More recently, the Army has used stop-loss to maintain the cohesion of military units, keeping together personnel as they train and deploy to Iraq and Afghanistan.
The Army now aims to achieve the same goal by offering monetary incentives for soldiers to voluntarily extend their service until 60 days after the end of overseas deployments, said Maj. Gen. Gina Farrisee, the Army's director of military personnel management. The details of such an incentive plan have not been released.