President Donald Trump tweeted Wednesday that the U.S. military would not allow transgender troops to serve, citing the “the tremendous medical costs and disruption.”

In a series of tweets, Trump tweeted that the U.S. government “will not accept transgender individuals to serve in the military in any capacity.”

The president said that the military “must be focused on decisive and overwhelming victory” and allowing transgender individuals would cause “tremendous medical costs and disruption.”

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

A Rand Corporation study of the issue last year estimated that there were about 4,000 transgender people serving in the military.

The study found that transition-related treatment would increase military health system costs from $2.4 million to $8.4 million a year, 0.038 percent to 0.134 percent of military health care costs.

Reaction from members of Congress was swift, and not only from the opposing party.

Rep. Ileana Ros-Lehtinen, whose son is transgender, said “No American, no matter their sexual orientation or gender identity, should be prohibited from honor + privilege of serving our nation.”

No American, no matter their sexual orientation or gender identity, should be prohibited from honor + privilege of serving our nation #LGBT

— Ileana Ros-Lehtinen (@RosLehtinen) July 26, 2017

Asked about Trump’s tweets during an interview with CNN, Alabama Republican Sen. Richard Shelby responded, “You ought to treat everybody fairly and give everybody a chance to serve.”

Fellow Republican Sen. Joni Ernst of Iowa also criticized the decision in a statement to NBC News saying “while she believes taxpayers shouldn’t cover the costs associated with gender reassignment surgery, Americans who are qualified who are qualified and can meet the standards to serve in the military should be afforded that opportunity.”

Colorado Rep. Ken Buck, a Republican who previously led a hate crime prosecution in the murder of a transgender woman, criticized the tweets according to the Denver Post.

“America needs a military comprised of patriots willing to sacrifice for this country,” he said. “Any American who is physically and emotionally qualified should be allowed to serve.”

In an interview on Boston Public Radio, Democratic Rep. Seth Moulton called the decision “despicable.”

“It sounds like the same argument used against African-Americans, used against gays, used against whoever else … people who are willing to put their lives on the country, which by the way, is far more than President Trump has ever been willing to do,” Moulton said. “He got five deferments to avoid serving, himself.”

Democrats piled on, using words like “bigotry” and “shameful.”:

#Trans soldiers have been fighting, dying 4 our country in our military. They deserve our thanks & support, not this bigotry & hatred @POTUS pic.twitter.com/TtATayhmYu

— Rep. Ted Lieu (@RepTedLieu) July 26, 2017

A disgraceful slap in the face to the thousands of transgender troops who are actively serving our country & to all who aspire to serve. pic.twitter.com/AYDpwh0NCN

— Rep. Shea-Porter (@RepSheaPorter) July 26, 2017

America is strongest when all who love our country can serve. @POTUS attack on #transgender servicemembers is shameful. I stand with them. pic.twitter.com/no1jEg9kYF

— Jim McGovern (@RepMcGovern) July 26, 2017

Rep. Dan Kildee of Michigan pointed out that Trump’s announcement came on the anniversary of a major civil rights milestone.

On this day in 1948, Pres. Truman abolished racial discrimination in the military.

Today @POTUS banned transgender Americans from serving.

— Rep. Dan Kildee (@RepDanKildee) July 26, 2017

House Minority Leader Nancy Pelosi said Trump’s announcement marked a “dark day for thousands of heroes in our military and for our entire country.”

“This morning’s tweets reveal a President with no loyalty to the courageous men and women in uniform who risk their lives to defend our freedoms,” Pelosi said in a statement.  “This disgusting ban will weaken our military and the nation it defends. Once again, President Trump has shown his conduct is driven not by honor, decency, or national security, but by raw prejudice.

Democratic Rep. Scott Peters of California said he would file an amendment to block Trump’s ban on transgender individuals

“I can’t think of anything more backwards than turning away a brave, qualified American who wants to serve in our all-volunteer military because of their gender identity,” Peters said in a statement.

Trump’s decision comes after an amendment to the National Defense Authorization Act that would have prevented the Pentagon from paying for hormone therapy and gender reassignment surgery was defeated last week, with 24 Republicans voting against it.

Trump’s announcement also comes after Defense Secretary James Mattis announced he would allow military chiefs to delay enlistment of transgender individuals by six months, the Military Times reported.

The move is a reversal of a policy of former Defense Secretary Ash Carter, who announced last year that transgender individuals would be allowed to serve in the military.

The new policy is to be implemented by the beginning of this month.

Correction July 27 11:55| A previous version misstated which state Rep. Dan Kildee represented.