American soldiers will have to serve up to 15 months in Iraq and Afghanistan instead of a year, the Pentagon has announced.
The move will allow the US military to maintain higher levels of forces in both countries, Defence Secretary Robert Gates said.
"This policy is a difficult but necessary interim step," he told a Pentagon news conference.
Mr. Gates said the problem was evident even before President Bush ordered an increase in troops for Iraq this year. Officials said the change became inevitable as the numbers of extra troops that were needed — and, most likely, the time the extra forces would have to stay — increased.
By ordering longer tours for all other Army units, the Pentagon will be able to maintain the current force levels for another year and still give soldiers a full year to rest, retrain and re-equip before having to go back to Iraq or Afghanistan, Mr. Gates said.
The new policy calls for soldiers to receive a minimum of one year at home between tours, the New York Times reports.
The shift, which doesn't apply to the Marine Corps, comes as 73 percent of Americans said Bush's plan for Iraq has made the situation there worse or has had no effect on the country's stability, according to a Bloomberg/Los Angeles Times poll.
The U.S. has 145,000 troops in Iraq, and 3,287 U.S. personnel have died there since the March 2003 invasion, according to Pentagon figures, Bloomberg reports.
In recent days, the Pentagon has notified National Guard brigades from four states that they are in line to deploy to Iraq for a second time, eliciting complaints from governors. Also, the Pentagon poured more than $1 billion into bonuses last year to keep soldiers and Marines in the military in the face of an unpopular war.
At a Pentagon news conference, Gates said that it was too early to estimate how long the troop buildup would last but that his new policy would give the Pentagon the capability to maintain the higher force levels until next April. Democrats in Congress, and some Republicans, oppose the buildup and are trying to force Bush to change course. In January, the administration indicated the buildup might begin to be reversed by late summer or fall.
Reaction on Capitol Hill to Gates' announcement was harsh, the AP reports.
Prepared by Alexander Timoshik