Marine Commandant General James Conway has emerged as one of the most outspoken critics of lifting the ban on gays and lesbians serving openly in the US military.

A former senior Pentagon official told the Washington Times that Conway had been more outspoken than other service chiefs, saying: “He feels very strongly that [removing the ban] would be disruptive, and he opposes it.”

Many military seniors are said to be apprehensive about lifting a ban at a time of stress for the service, although President Barack Obama has promised to repeal it.

The Washington Times wrote that Conway’s spokesman would not confirm whether he had voiced his opposition to Obama’s plans.

The spokesman said: “Our Marines are currently engaged in two fights, and our focus should not be drawn away from those priorities. When the time is right, we have full confidence that we will be asked to provide the best military advice concerning the readiness of the Corps as it relates to this issue.”

Conway is thought to be the only chief to have carried out a survey of his generals on their feelings about lifting the ban.

Aaron Belkin, director of the Palm Centre, which has carried out much research on the ban, said that Conway’s reported comments could be seen as a precursor to arguments which will be used in Congressional hearings, namely that the military is focusing on the wars in Iraq and Afghanistan.

He said: “It does appear that these comments are a warning shot to proponents, including the White House.”

Others expressed concern that Conway’s opposition could raise thorny questions of civilian control over the military.

“The president has declared which way policy is heading,” said Professor Diane Mazur. “There is no faster way for a commander-in-chief to lose the respect of those serving under him than to allow his service chiefs to march in an opposite direction.”

Mazur is professor of law at the University of Florida and an expert on civil-military relations.

The ban means that gay and lesbian servicemembers cannot be asked about their sexual orientation but can be fired if it is revealed.