Speaker Johnson says transgender women won't be allowed to use women’s restrooms in Capitol

This also applies to changing rooms and locker rooms, Johnson said.

House Speaker Mike Johnson said transgender women cannot use women's restrooms in the Capitol and House office buildings. This also applies to changing rooms and locker rooms, Johnson said.

"All single-sex facilities in the Capitol and House Office Buildings — such as restrooms, changing rooms, and locker rooms — are reserved for individuals of that biological sex," the statement said Wednesday.

Johnson continued, "It is important to note that each Member office has its own private restroom, and unisex restrooms are available throughout the Capitol."

After winning her election earlier this month to be Delaware's sole representative in the House, Rep.-elect Sarah McBride will be the first openly trans member of Congress.

McBride responded to Johnson Wednesday by saying, "I’m not here to fight about bathrooms. I’m here to fight for Delawareans and to bring down costs facing families. Like all members, I will follow the rules as outlined by Speaker Johnson, even if I disagree with them."

It's unclear what will happen with South Carolina GOP Rep. Nancy Mace's bill that would ban transgender women from using women's restrooms in the Capitol, but she celebrated the speaker's decision as a victory for women's rights.

"I am proud to be a woman, and today, women won," Mace said. "And I'm not going to stop there. I have another bill that I've drafted, and I will file it when we get back in December -- if you're a federally funded educational institution, school, etcetera, women have to be protected, too, in private spaces. So this is just the start."

Democratic Rep. Alexandria Ocasio-Cortez called the decision "disgusting."

"Because if you ask them, 'What is your plan on how to enforce this?' they won't come up with an answer. And what it inevitably results in are women and girls who are primed for assault because they want, because people are going to want to check their private parts in suspecting who is trans and who is cis and who's doing what," she said.

Mace had said earlier that her bill she introduced was "absolutely" in response to McBride entering Congress.

"Yes, and absolutely. And then some," Mace told reporters at the Capitol. "I'm not going to stand for a man, you know, someone with a penis, in the women's locker room," she said.

Asked by ABC News on Wednesday if she had met with McBride over the issue, Mace said she had not.

"She doesn't get a say in this. This is about women's rights, and at some point we have to draw a line in the sand," Mace said. "I'm somebody who's very socially sensible. I voted for gay marriage, not once, but twice."

"He was born a biological male," she said of McBride. "It's not -- I'm not into pronouns. I don't care. I try to be as respectful as I can. I'll even work with with him or her on legislation. I work with anyone who's willing to work with me, but I'm not going to play into this gender ideology, this wackadoo lunatic, crazy thing that men want to force on women."

In terms of how Johnson plans to enforce this policy is not entirely clear, but the speaker has "general control" of facilities, according to House rules.

"This effort to distract from the real issues facing this country hasn't distracted me over the last several days, as I've remained hard at work preparing to represent the greatest state in the union come January," McBride said in a statement Wednesday.

In response to Mace, McBride has received support from House Minority Leader Hakeem Jeffries and the Democratic Women's Caucus.

"Instead of focusing on lowering costs and real solutions to improve the health and safety of women and families, Republicans are cruelly attacking our new Member to distract from their inability to govern. We won't stand for it," a post from the women's caucus read on X.

Jeffries said Republicans are bullying McBride.

"This incoming, small, House Republican Conference majority is beginning to transition to the new Congress by bullying a member of Congress," Jeffries said Tuesday. "This is what we're doing? This is the lesson that you've drawn from the election in November? This is your priority, that you want to bully a member of Congress, as opposed to welcoming her to join this body so that all of us can work together to get things done and deliver real results for the American people?"

ABC News' Isabella Murray, John Parkinson and Chris Boccia contributed to this report.