House Republican leaders will take an unprecedented step Tuesday when they are expected to block Republican Rep. Anna Paulina Luna’s bipartisan discharge petition to allow proxy voting for new lawmaker parents up to 12 weeks after giving birth — the latest move in a weekslong internal House GOP clash.

Republican leaders inserted specific language into the joint “rule” — a procedural maneuver to advance legislation — which says the discharge petition by Luna, a hard-line Republican, and other similar bills that would address proxy voting are out of order.

Tuesday afternoon’s vote is on the joint rule — which also includes other unrelated legislation. Luna is expected to vote against the rule. If others join her, the House could be paralyzed from moving on legislation.

Luna’s legislation seeks to allow new mothers and fathers in the House to vote on legislation remotely. Luna had a child in 2023 as she was serving in Congress.

“I am doing this because I believe this governing body needs to change for the better and young American parents need to be heard in the halls of Congress,” Luna said last week.

This extraordinary move from GOP leaders to block the legislation comes after Luna received 218 signatures on her resolution — enough needed to force the House to vote on the measure. Lawmakers use discharge petitions to circumvent leadership, who determine what legislation comes to the floor.

Speaker Mike Johnson and Luna have been at odds over proxy voting for new parents. The speaker has argued the effort is unconstitutional and made his case during the closed GOP conference meeting Tuesday morning, sources told ABC News.

Johnson has argued that proxy voting is the start of a slippery slope that could lead to more and more members voting remotely. Proxy voting was used during the COVID-19 pandemic, which many Republicans were against.

“I believe it’s unconstitutional. I believe it violates more than two centuries of tradition in the institution, and I think that it opens a Pandora’s box where, ultimately, maybe no one is here, and we’re all voting remotely by AI or something. I don’t know. I don’t think that’s what Congress is supposed to be,” Johnson said at a news conference last week.

Despite some Republican support for the bill, Johnson said “as the leader of this institution and the one who’s supposed to protect it, I don’t feel like I can get on board with that.”

“This is a deliberative body. You cannot deliberate with your colleagues if you’re out somewhere else. Now, there are family circumstances that make it difficult for people to attend votes. I understand that. I’ve had them myself,” he said.

Luna said in a post on X Tuesday that she asked that the legislation just cover new moms to vote by proxy “and they still said no.”

“The argument here is no longer making sense,” Luna wrote. “They say it is unconstitutional yet they voted by proxy.”

The vote comes a day after Luna resigned from the ultra-conservative House Freedom Caucus over her legislation, according to a letter obtained by ABC News.

“With a heavy heart, I am resigning from the Freedom Caucus. I cannot remain part of a caucus where a select few operate outside its guidelines, misuse its name, broker backroom deals that undermine its core values and where the lines of compromise and transaction are blurred, disparage me to the press, and encourage misrepresentation of me to the American people,” she wrote in the letter.