The US military opened up some dangerous jobs to female troops but stopped short of repealing a ban on women serving in combat, despite a decade of war where women fought and died on the battlefield.

The Pentagon announced incremental changes that will allow women to serve in more than 14,000 jobs, mostly in the Army and Marine Corps, that had previously been closed to female service members.

But the Pentagon's overall prohibition against women in ground combat will remain, denying female troops the chance to join infantry and armor units as well as special forces.

The Pentagon said the changes would be reviewed within months and likely clear the way for opening more doors to women in the future.

Defense Secretary Leon Panetta "believes that this is the beginning, not the end of a process," his spokesman George Little told a news conference.

"The services will continue to review positions and requirements to determine what additional positions may be open to women," he said.

Some activists and senior officers have urged a more dramatic change to reflect the reality of the wars in Iraq and Afghanistan, where a lack of clearly defined front lines placed women in the middle of the fight.

Since 2001, about 280,000 American women have served in Iraq and Afghanistan, about 12 percent of all troops who deployed, with 144 female troops killed in the wars, including 79 in combat, according to the Pentagon.

"It's a baby step," said Donna McAleer, a graduate of the military academy at West Point and author who has called for repealing the combat ban.

The result was not a surprise for a large organization that over the years has tended to take a cautious approach to changing social standards, she said.

The decision "ducks the issue of opening up ground combat and the requisite occupations in those units," she told AFP.

As a result, women will still miss out on battlefield positions needed to win promotion to the decision-making top brass, she said.

Only about six percent of all of the Army's general officers are females, even though women comprise about 15 percent of the force.

Pentagon officials, however, defended their deliberate approach.

"It may appear too slow to some. But I see this as a great step forward," said Vee Penrod, deputy assistant secretary of defense for military personnel policy.

Until now, women were confined to serving in brigades to keep them away from possible combat. The changes will allow female intelligence officers and other specialists to serve in battalions, units of about 800 troops instead of the 3,500-strong brigades, which are more likely to face combat.

The new rules also will open up more than a dozen positions that previously were off-limits, including tank mechanic jobs, rocket launcher crew posts and artillery radar operators.

The changes are expected to take effect within a couple of months, unless Congress decides to block them.

Even under the new policy, about 238,000 jobs in the military will remain closed to women because of the combat prohibition, said Major General Gary Patton, head of military personnel policy.

The successful performance of female warriors in the 1990-91 Gulf war helped prompt an earlier wave of reform that led to women serving in combat aircraft and naval warships.

Unlike the Army and Marines, the US Air Force and Navy have few remaining restrictions on female service members, with a 2010 decision allowing women to serve on submarines.

Opponents of allowing women in ground combat argue that they lack the required physical strength, that their presence could prove disruptive to the "cohesion" of combat units and that mothers should not be placed in harm's way.

But advocates say the military's experience in Iraq and Afghanistan has shown otherwise.

Officials said Thursday the new policy would also encourage the armed services to develop "gender neutral" physical standards for jobs, which might eventually lead to easing current restrictions on women's roles.

The policy change comes months after the US military ended a ban on openly gay troops serving in uniform, following years of political debate and a survey of troops.