A group of active-duty troops, a Naval Academy midshipman and a teenage ROTC member on Thursday asked a federal judge to block the Trump administration from moving forward with a ban on transgender military service.

The motion for a preliminary injunction, filed in a D.C. district court with the backing of former top Obama administration officials, seeks to halt any moves by the Pentagon and Coast Guard that could harm the careers of transgender service members while the case is being heard.

The new filing included supporting legal statements arguing against a ban by architects of the current year-old open transgender policy, including former Air Force Secretary Deborah James, former Navy Secretary Ray Mabus, former Army Secretary Eric Fanning, and Brad Carson, who served as undersecretary of personnel and readiness.

New plaintiff, Regan Kibby from U.S. Naval Academy, says preliminary injunction needed to stop ban before it "ruins transgender service members' lives."

An injunction "would stop the Pentagon and all the branches of the military from taking any negative actions against transgender service members in any respect and it would also require that transgender people seeking to enlist in the military would be able to and treated equally," said Shannon Minter, the legal director of the National Center for Lesbian Rights, which is sponsoring the lawsuit along with GLBTQ Legal Advocates and Defenders.

The former Obama administration service secretaries all said they were not aware of any harm to the military caused by the decision last year to allow open service following a study.

"To the contrary, I am aware of commanders who believed that transgender service members under their command were capable and well-qualified to serve," said Fanning, who was the first openly gay service secretary.

James and Mabus, a former Democratic governor of Mississippi, both said the order by Trump to return to the previous policy of banning transgender service would damage the military by preventing the recruitment of qualified personnel and eroding trust in leadership.

"Some transgender service members are senior and hold important leadership positions. The military has invested significant resources in the education and training of these personnel," James said in the filing. "Those resources are squandered when they are separated for reasons unrelated to their ability or performance."

Trump on Aug. 25 ordered the Pentagon to start rolling back the Obama administration policy of open transgender service and gave Defense Secretary Jim Mattis six months to decide how to handle currently serving troops who have come out, and to end coverage of gender reassignment surgeries.

"The president gave me the time to look at this and obviously he wanted me to do something or he would have said I want something done tomorrow," Mattis said Thursday. "He's told me what he wants in broad terms and now he's leaving it up to me."

The D.C. suit was filed Aug. 9 following a series of tweets by Trump declaring that transgender troops would no longer be able to serve in any capacity due to costs and disruption.

On Monday, two other federal lawsuits against Trump, Mattis and other top administration officials were filed in Maryland and Washington state.

Attorneys for one of the suits representing a soldier and two prospective military recruits and filed by Lambda Legal and OutServe-SLDN said Thursday they too could soon seek an injunction to halt the administration from moving forward.

"That is a strategy we are considering now and we are considering what scope of relief we would ask for," said Peter Perkowski, counsel for OutServe-SLDN.