People who identify as “transgender” may not serve in the U.S. Military “in any capacity.” President Donald Trump tweeted the news Wednesday morning. 

“Our military must be focused on decisive and overwhelming victory,” he said. It “cannot be burdened with the tremendous medical costs and disruption that transgender in the military would entail.”

After consultation with my Generals and military experts, please be advised that the United States Government will not accept or allow……

— Donald J. Trump (@realDonaldTrump) July 26, 2017

….Transgender individuals to serve in any capacity in the U.S. Military. Our military must be focused on decisive and overwhelming…..

— Donald J. Trump (@realDonaldTrump) July 26, 2017

….victory and cannot be burdened with the tremendous medical costs and disruption that transgender in the military would entail. Thank you

— Donald J. Trump (@realDonaldTrump) July 26, 2017

The announcement comes shortly after GOP lawmakers in the House increased efforts to block military funding of transition treatments. Republican Rep. Vicky Hartzler of Montana wrote an amendment that would do just that. Transition treatment would cost the military $3.7 billion over the next 10 years, The Daily Signal reported. But in mid-July the amendment failed by a small margin, after 24 Republican lawmakers joined House Democrats in voting it down.

Last year former Secretary of Defense Ash Carter announced that military members could identify as transgender. Starting July 1, 2017, men who identify as women, and women who identify as men, were to be able to join the military. This opened up the military to costly treatments and surgery. It also implied that other military personnel must accept a person’s gender preference rather than their biological sex.

In late June, Defense Secretary James Mattis halted that policy. As reported by the Associated Press, he wanted to give military leaders more time to assess the effects such a policy would have on “readiness and lethality.”

Pro-LGBT advocacy group GLAAD said over 15,000 military members identify as transgender. “This ban will cause a huge disruption,” the group tweeted. American Civil Liberties Union attorney Joshua Block said “the ACLU is examining our options on how to fight this.”

Tony Perkins of Family Research Council lauded the move. 

“The last thing we should be doing is diverting billions of dollars from mission-critical training to something as controversial as gender reassignment surgery,” he said. 

Trump’s announcement “has shown once again that our nation’s military is no longer marching to the liberal drumbeat” of the Obama administration, Perkins added in a Wednesday conference call with members of the media. 

Joining Perkins, Hartzler said “our military service is a privilege, it’s not a right. We need to be sure every soldier is deployable.”

In addition to costing billions of dollars that could be used for important equipment, the Obama-era policy “was a real threat to readiness,” she said.

Service members who go through “lengthy surgery and recovery time” as well as hormone treatments cannot be deployed, Hartzler said. “It’s not fair to ask other soldiers to be deployed in their stead.”

She noted other conditions that may require surgery or compromise one’s health also keep people from military service. Hartzler listed asthma, color blindness and flat feet as examples. 

Allowing members to serve openly as members of the opposite sex has also “been a threat to unit cohesion and morale,” she said. For instance, members of the opposite sex showering with their unit before they have sex-change surgery.

“That’s not what a lot of soldiers signed up for.”

Hartzler said she hasn’t seen details on how military members currently openly identifying as transgender will be affected by Trump’s announcement. She said that information would be determined in the “coming days.”