Leon Panetta

WASHINGTON — The Pentagon is lifting its ban on women serving in combat, opening hundreds of thousands of front-line positions and potentially elite commando jobs after generations of limits on their service, defense officials said Wednesday.

The changes, set to be announced Thursday by Defense Secretary Leon Panetta, will not happen overnight. The services must now develop plans for allowing women to seek the combat positions, a senior military official said. Some jobs may open as soon as this year, while assessments for others, such as special operations forces, including Navy SEALS and the Army’s Delta Force, may take longer. The services will have until January 2016 to make a case to that some positions should remain closed to women.

The groundbreaking move recommended by the Joint Chiefs of Staff overturns a 1994 rule prohibiting women from being assigned to smaller ground combat units.

There long has been opposition to putting women in combat, based on questions of whether they have the necessary strength and stamina for certain jobs, or whether their presence might hurt unit cohesion.

But as news of Panetta’s expected order got out, members of Congress, including the Senate Armed Services Committee chairman, Sen. Carl Levin, D-Mich., announced their support.

“It reflects the reality of 21st century military operations,” Levin said.

Sen. Jim Inhofe of Oklahoma, who will be the top Republican on the Armed Services panel, said, however, that he does not believe this will be a broad opening of combat roles for women because there are practical barriers that have to be overcome in order to protect the safety and privacy of all members of the military.

Panetta’s move comes in his final weeks as Pentagon chief and just days after President Barack Obama’s inaugural speech in which he spoke passionately about equal rights for all. Panetta’s decision could open more than 230,000 jobs, many in Army and Marine infantry units, to women.

SAN FRANCISCO — Four female service members filed a lawsuit Tuesday challenging the Pentagon’s ban on women serving in combat, hoping the move will add pressure to drop the policy just as officials are gauging the effect that lifting the prohibition will have on morale.

The lawsuit, filed in federal court in San Francisco, is the second one this year over the 1994 rule that bars women from being assigned to ground combat units.

The legal effort comes less than a year after the ban on gays serving openly was lifted and as officials are surveying Marines about whether women would be a distraction in ground combat units.

“I’m trying to get rid of the ban with a sharp poke,” said U.S. Army Staff Sgt. Jennifer Hunt, who was among the plaintiffs in the latest lawsuit and was injured in 2007 when her Humvee ran over an improvised explosive device in Iraq.

Hunt and the other three women said the policy unfairly blocks them from promotions and other advancements open to men in combat.

Women comprise 14 percent of the 1.4 million active military personnel. The lawsuit alleges that women are barred from 238,000 positions across the Armed Forces.

At a Washington, D.C., news conference, Pentagon press secretary George Little said Defense Secretary Leon Panetta has opened about 14,500 combat positions to women.

“And he has directed the services to explore the possibility of opening additional roles for women in the military,” Little said. “His record is very strong on this issue.”

American Civil Liberties Union Ariela Migdal, who represents the four women, said Panetta’s actions weren’t enough. She called for an end to the combat ban. “These tweaks and minor changes on the margins do a disservice to all the women who serve,” she said.

“It falls short,” she said. “It is not enough.”

WASHINGTON — Defense officials say Pentagon chief Leon Panetta will certify that gays may serve openly in the armed services. News of his decision comes two weeks after top military leaders agreed that repealing the 17-year-old ban will not hurt military readiness.

The decision is not unexpected. The Pentagon has conducted months of internal studies and training to gauge how troops would react to the change triggered by a law passed by Congress and signed by President Barack Obama in December.

The Pentagon announcement is expected Friday, and Obama is expected to endorse it.

Repeal of the ban would become effective 60 days after certification, which could open the military to gays by the end of September.

The officials spoke on condition of anonymity because the decision has not been made public.