The former Republican mayor of New York City, Mike Bloomberg, has come under fire for 2016 comments referring to transgender women as men in dresses.

Bloomberg is currently running in the Democratic presidential primary, and his campaign has released a plan for LGBTQ equality. The plan mentioned transgender people, saying that trans people “face intersecting barriers” in health care and that Bloomberg wants to specifically address violence and discrimination against transgender women of color.

Related: That administrator who demanded a trans student pee in front of him? He’s back on the job.

But now a video has surfaced of Bloomberg responding to a question about Brexit by saying that people who live in the Midwest are too uneducated to understand transgender equality.

“I don’t know how many of you are familiar with the bathroom issue in the United States,” he said during a panel discussion at Oxford University, which is in the United Kingdom. Debates on transgender rights regularly appear in mainstream media in the U.K. and are perhaps more heated than in the U.S. “Anybody know what I’m talking about?”

“If you want to know if somebody is a good salesman, give them the job of going to the Midwest and picking a town and selling to that town the concept that some man wearing a dress should be in a locker room with their daughter,” he said. “If you can sell that, you can sell anything.”

The idea of transgender women using bathrooms and other facilities with underage girls – with the implication that trans women will molest children – has been one of the most consistently used attacks on transgender rights by the religious right.

He then imagined a conversation between a hypothetical Oxford scholar and a moron from flyover country. “I mean, they just look at you and they say, ‘What on earth are you talking about?’ And you say, ‘Well, this person identifies his… or her gender as different than what’s on their birth certificate.’ And they say, ‘What do you mean? You’re either born this or you’re born that.'”

Bloomberg didn’t stick with the birth certificate as the standard of determining one’s gender. He proceeded to say it depends on what a prison guard sees when you “drop your trousers.”

“You know, I will say in our prison system in New York City we have to have the policy when you walk in, you know, drop your trousers, you go this way, you go that way. That’s it,” he said, adding that prison is “a practical case of when you have to make a decision,” implying that there is no way to tell what someone’s gender identity is other than examining genitalia.

Federal law under the Obama administration required that the question of where to house transgender prisoners be considered on a case-by-case basis and that “serious consideration” be given to “a transgender inmate’s own views with respect to his or her own safety,” guidelines that were rolled back in the Trump administration.

According to Logo, Bloomberg promised last week to bring back those Obama era guidelines.

In a statement, Bloomberg’s campaign said he is serious about wanting to pass the Equality Act to ensure “transgender people have access to affirming healthcare and working to end the crisis of violence against transgender women.”

“Mike is running to defeat Donald Trump and reverse the many policies he has implemented that attack the rights of the transgender community,” the statement said.

Here's @MikeBloomberg in December 2016 at Oxford explaining how trans rights simply won't fly in the midwest because only the "intelligentsia" can understand why "some man wearing a dress should be in a locker room with their daughter." pic.twitter.com/g6aa8aB1jq — Walker Bragman (@WalkerBragman) February 6, 2020

Here’s the text of the clip: