(New York City) More than 1,000 retired military officers, including several who were top commanders, are urging President Barack Obama and Congress to maintain the law that bars gays from serving openly in the armed forces.

Obama is consulting with the Pentagon on the issue and says he supports eventual repeal of the “don’t ask, don’t tell” policy, which prohibits gays in the military from being open about their sexual orientation. A bill that would allow gays to serve openly has been introduced in Congress.

A statement issued by the retired officers Tuesday said passage of that bill “would undermine recruiting and retention, impact leadership at all levels, have adverse effects on the willingness of parents who lend their sons and daughters to military service, and eventually break the All-Volunteer Force.”

Among the signatories were Gen. Carl E. Mundy, Jr., a former commandant of the Marine Corps; Adm. Leighton W. Smith, a former commander of U.S. Naval Forces Europe; Gen. Charles A. Horner, who commanded U.S. aerial forces during the 1990-91 Gulf War; and Adm. Jerome L. Johnson, a former vice chief of Naval Operations.

The retired officers said they strongly supported the principle that “homosexuality is incompatible with military service” and warned that repeal of current law could jeopardize morale and “unit cohesion.”

Mundy said in a telephone interview that he believed a “large segment” of currently serving officers shared the views expressed in the statement.

“We just see a great many downsides to attempting to enforce on the military something I don’t know is widely accepted in American society,” he said.

The statement was criticized by Aubrey Sarvis, executive director of the Servicemembers Legal Defense Network, an advocacy group seeking equal treatment of gays in the military.

“The signers of this petition are mired in the fears and politics of the past,” Sarvis said. “More than 75 percent of the American public, including most younger service members as well as many active duty flag officers, realize the question is not if ‘don’t ask, don’t tell’ is repealed, but when and how.”

On Sunday, Defense Secretary Robert Gates indicated that executive branch action on “don’t ask, don’t tell” was not imminent because he and Obama have “a lot on our plates right now.”

“Let’s push that one down the road a little bit,” Gates said on “Fox News Sunday.”

Sarvis, who criticized Gates’ remarks, said Obama should press for repeal of “don’t ask, don’t tell” as part of the upcoming Defense Department budget process.

“The most important factor in lifting a gay ban is a clear signal from senior leadership,” said Dr. Nathaniel Frank, senior research fellow at the Palm Center, a think tank at the University of California, Santa Barbara, that studies issues involving gays and the military.

“Everyone knows it’s just a matter of time before the gay ban falls, so for officers to come out and say ‘Gays are a threat to the military’ could cause the very problems that they ostensibly fear,” Frank said.

The campaign to gather the retired officers’ signatures was organized by the Livonia, Mich.-based Center for Military Readiness. Its president, Elaine Donnelly, has been an outspoken foe of gays serving in the military and testified before Congress on the matter last year.

The “don’t ask, don’t tell” policy was put in place after President Bill Clinton tried to lift the ban on gay service members in 1993. Under the policy, the military does not ask recruits about their sexual orientation, while service members are banned from saying they are gay or bisexual, engaging in homosexual activity or trying to marry a member of the same sex.