US lawmaker Matt Gaetz, seen at the Capitol on September 30, 2023, has vowed to seek the removal of House Speaker Kevin McCarthy
US lawmaker Matt Gaetz, seen at the Capitol on September 30, 2023, has vowed to seek the removal of House Speaker Kevin McCarthy. AFP

A far-right Republican lawmaker launched a bid on Monday to oust US House Speaker Kevin McCarthy from his post, triggering the most serious showdown yet within the Republican party as it battles to contain firebrand supporters of ex-president Donald Trump.

Matt Gaetz, a representative from Florida, entered his resolution from the House floor "declaring the office of Speaker of the House of Representatives to be vacant."

The resolution, which requires a majority to pass, could force a vote within days and comes after McCarthy brokered a last-gasp deal with Democrats over the weekend to keep the government funded for another 45 days.

Gaetz has been vowing retribution since the shutdown deal was struck.

"Bring it on," McCarthy quickly responded to the motion to vacate on X, formerly known as Twitter.

Gaetz is a leading figure within the small group of far-right Republican legislators who brought the government to the brink of shutdown with their refusal to adopt fresh federal funding without deep spending cuts.

The group also opposes sending additional support to Ukraine, saying the money would be better spent in the United States on combatting illegal immigration.

The hardliners hold a de facto veto over legislation in the House, given Republicans' narrow victory in the midterm elections last November.

"The American people are tired of Washington DC not having a budget, running $2 trillion annual deficits sitting atop a $33 trillion debt," Gaetz told reporters Monday after introducing his motion.

"If this country's going down, I'm going down fighting," he said.

McCarthy "doesn't have my support anymore, and he doesn't have the support of a requisite number of Republicans to continue as the Republican Speaker," Gaetz continued.

In order to gain the speaker's gavel in January, McCarthy was forced to make concessions to the far-right bloc, including a rule change that allows one member to file a such a "motion to vacate."

It took a historic 15 rounds of voting for a speaker in January for McCarthy to finally win the position.

The timeline for next steps on Gaetz's resolution is variable, and it is not yet clear if Democrats would come to McCarthy's aid.

On Monday, Gaetz said that "if the Democrats want to own Kevin McCarthy, they can have him. Because one thing I'm at peace with is -- when we stand here a week from now, I won't own Kevin McCarthy anymore."

US President Joe Biden has lambasted both McCarthy and the hardliners for failing to live up to an agreement forged around a debt crisis months ago that was meant to avoid a damaging shutdown fight -- and for stripping out support for Ukraine.

"Stop playing games, get this done," Biden said during a press conference on Sunday, adding that he was "sick and tired of the brinksmanship, and so are the American people."

Gaetz on Monday called for the border funding and Ukraine aid to be voted on separately.

"Regardless of how you feel about Ukraine money or border money, these two things should not be lumped together. They deserve their own dignity and their own vote," he said.