WASHINGTON, D.C. — President Donald Trump said his administration reinstituted a ban against most transgender people serving in the military because some of them take prescription medicine, claiming erroneously that the armed services prohibit drug use.

Trump was asked why he implemented the ban, which took effect in March, during an interview with ITV’s “Good Morning Britain” broadcast earlier on Wednesday.

“Because they take massive amounts of drugs, they have to,” Trump said. “You’re not allowed to take drugs, you’re in the military you’re not allowed to take any drugs. And they have to after the operation, they have to, they have no choice, they have to. You would actually to break rules and regulations in order to have that.” The military doesn’t prohibit service members from taking prescription medicines, including drugs prescribed for psychotropic conditions such as depression and anxiety.

The Navy, in fact, changed its policy late last year to allow pilots and other aircrew on such drugs to continue flying.

The Pentagon didn’t immediately respond to a request for comment.

Some transgender people choose to take prescription hormones that change their sexual characteristics, and some also undergo sexual reassignment surgery, but the term “transgender” isn’t dependent on medical procedures.

Challenged by interviewer Piers Morgan, who said that the cost of prescription hormones for transgender service members was “minuscule” compared to the Pentagon’s overall budget, Trump complained about the cost and burden of sexual reassignment surgery.

“Look, massive amounts and also people going in and asking for the operation —you know the operation is 200,000, 250,000 dollars, and getting the operation, the recovery period is long and they have to take large amounts of drugs after that for whatever reason —but large amounts, and that’s not the way it is,” Trump said. “I mean you can’t do that. So I said, yeah, when it came time to make a decision on that and because of the drugs and also because of the cost of the operation.”

Medical services specific to transgender people cost the military about $8 million between 2016 and February of this year, including 161 surgical procedures, according to data reported by USA Today. The newspaper reported that about 1,524 troops had been diagnosed with gender dysphoria since July 1, 2016, when Trump’s predecessor Barack Obama lifted a military ban on transgender people openly serving and allowed them to seek medical treatment. Total military spending for health care was estimated to be about $44 billion in fiscal 2018, according to the Pentagon’s comptroller.

Trump tweeted in July 2017 that he would reimpose the transgender ban, but it was delayed by court challenges and didn’t take effect until April. The policy allows transgender service members who were already taking hormones or undergoing sexual reassignment surgery to continue receiving care, but prohibits future enlistments by anyone diagnosed with gender dysphoria.

Transgender service members who weren’t receiving medical care as of the date of the ban are required to serve in their birth gender.