Representative Matt Gaetz, the far-right Republican from Florida, said on Sunday that he would move this week to remove Speaker Kevin McCarthy from his leadership post, promising to follow through on weeks of threats to try ousting him for working with Democrats to keep the government funded.
Mr. Gaetz’s announcement came the day after Mr. McCarthy, in a stunning reversal, steered around Republican opposition to a stopgap spending plan and turned to Democrats to help him push legislation through the House to avert a shutdown. The California Republican said he knew he was putting his speakership at risk by doing so, and dared his detractors to make a move against him.
In an interview on CNN’s “State of the Union” on Sunday, Mr. Gaetz, Mr. McCarthy’s main tormentor, said he would do just that. He said he would soon bring up a measure called a “motion to vacate,” which prompts a snap vote on whether to keep the speaker in his post.
“I think we need to rip off the Band-Aid,” Mr. Gaetz said. “I think we need to move on with new leadership that can be trustworthy.”
Mr. McCarthy shrugged off the threat, predicting that Mr. Gaetz’s effort to remove him would fail and was motivated by a petty grudge rather than a substantive dispute.
“I’ll survive. You know this is personal with Matt,” he said during an interview on CBS’s “Face the Nation,” accusing Mr. Gaetz of being “more interested in securing TV interviews than doing something. He wanted to push us into a shutdown.”
“So be it, bring it on. Let’s get over with it and let’s start governing,” Mr. McCarthy added. “If he’s upset because he tried to push us into a shutdown and I made sure the government didn’t shut down, then let’s have that fight.”
Mr. Gaetz had long threatened to oust Mr. McCarthy for going back on several promises he made to Republican hard-liners to win their support to become speaker, including demands for deep spending cuts. In the interview, he accused Mr. McCarthy of lying to his G.O.P. members during spending negotiations, and making a “secret deal” with Democrats concerning funding for Ukraine, which he and dozens of other conservative Republicans have opposed.
“Nobody trusts Kevin McCarthy,” he added, predicting that the only way Mr. McCarthy would remain speaker by week’s end is “if Democrats bail him out.”
Though most House Republicans still support keeping Mr. McCarthy on as speaker, Mr. Gaetz’s plans pose an existential threat to his tenure because of the slim majority the G.O.P. holds in the chamber. If Democrats were to vote against Mr. McCarthy — as is almost always the case when a speaker of the opposing party is being elected — Mr. Gaetz would need only a handful of Republicans to join the opposition to remove him from the post, which requires a simple majority vote.
To avoid that fate, at least some Democrats would have to either vote to keep Mr. McCarthy in office, or simply skip the vote or vote “present” — neither for nor against. That would lower the threshold for a majority and make it easier to defeat Mr. Gaetz’s motion.
It is not clear whether Democrats would help Mr. McCarthy, however, particularly because he recently announced that he was opening an impeachment inquiry into President Biden despite lacking any evidence of wrongdoing. Most Democrats regard Mr. McCarthy as an untrustworthy figure who has spent months catering to the whims of his right wing, turning to Democrats only when his back is up against the wall, as he did in the spring to avoid a federal debt default and again on Saturday, during the waning hours of the fiscal year, to keep the government open.
“I believe that it’s up to the Republican conference to determine their own leadership and deal with their own problems, but it’s not up to Democrats to save Republicans,” Representative Alexandria Ocasio-Cortez, Democrat of New York, said on “State of the Union.”
Ms. Ocasio-Cortez said she would “absolutely” vote to remove Mr. McCarthy, calling him a weak leader who had lost control of the chamber’s Republicans and voicing skepticism that he could offer Democrats anything to gain their assistance.
“I don’t think we give up votes for free,” she said.
Mr. McCarthy said in his “Face the Nation” interview that the House minority leader, Representative Hakeem Jeffries, Democrat of New York, had not indicated to him how he might vote on a motion to oust the speaker.
It is also unclear how many Republicans Mr. Gaetz might rally to vote against Mr. McCarthy over the next few days. Representative Byron Donalds, Republican of Florida, who has criticized Mr. McCarthy but also clashed with Mr. Gaetz in recent weeks, said during an interview on “Fox News Sunday” that he had not decided how he would vote on a motion to vacate.
“I think he is in trouble,” Mr. Donalds said of Mr. McCarthy, adding that he would “really have to think about” how he planned to vote.
Still, Mr. Gaetz expressed confidence that he would eventually rally enough votes among Democrats and Republicans to oust Mr. McCarthy as speaker, even if his opening attempt this week fails.
“I might not have them the first time, but I might have them before the 15th ballot,” Mr. Gaetz said on ABC’s “This Week,” making a pointed reference to the number of attempts it took Mr. McCarthy to secure his speakership in January. He added, “I am relentless, and I will continue to pursue this objective.”
Mr. Gaetz did not say who he would like to see replace Mr. McCarthy as speaker if he is deposed, arguing that it would be unfair to speculate while the House’s second-highest-ranking Republican, Representative Steve Scalise of Louisiana, is being treated for cancer.
“I want to see how Steve Scalise comes out of that,” Mr. Gaetz said.
That left open the possibility that the top post in the House could remain open for some time, with Mr. McCarthy forced out and nobody else able to muster the votes to replace him.
The situation has left mainstream Republicans, including those in politically competitive districts who have toiled to distance themselves from their party’s extreme right, fuming.
Representative Mike Lawler, Republican of New York, accused Mr. Gaetz of being “duplicitous” and engaging in “diatribe of delusional thinking.” In an interview on ABC that aired just after Mr. Gaetz’s appearance, he accused the Florida Republican of breaking faith with the House G.O.P. and its rules by pushing ahead with the motion to vacate when a majority of the chamber’s Republicans did not share his animus against Mr. McCarthy. He also argued that the move would undermine all of the work Republicans had done to advance their conservative policy agenda.
“This will all be torpedoed by one person who wants to put a motion to vacate for personal, political reasons,” Mr. Lawler said, noting, “We have to work together as a team.”
Chris Cameron contributed reporting.