U.S. House of Representatives Speaker Kevin McCarthy faced a direct threat to his leadership when hardline fellow Republican Representative Matt Gaetz called for a vote on Monday to oust him, injecting an additional element of chaos into Congress.

Gaetz, who has clashed with McCarthy for months, said he introduced a "motion to vacate" that would force a vote to remove McCarthy as speaker, though he has not floated an alternative leader for the chamber.

It is not clear whether he will succeed. Republicans control the chamber by a narrow 221-212 majority, and it would take as few as five defections to threaten McCarthy's hold on power, if all Democrats vote against him.

Gaetz and other far-right Republicans are angered that McCarthy relied on Democratic votes to pass a temporary funding extension on Saturday that headed off a partial government shutdown. A faction of about 20 Republicans, Gaetz included, had forced McCarthy's hand by repeatedly blocking other legislation.

McCarthy has called Gaetz's leadership challenge disruptive and has said he expects he will survive. "Bring it on," he wrote on the X platform, formerly Twitter.

Gaetz was one of more than a dozen far-right Republicans who repeatedly voted against McCarthy's bid for speaker in January. McCarthy ultimately secured the gavel after 15 rounds of voting.

As a condition of winning that January vote, McCarthy agreed to a rules change that allowed any one member to call for a vote to oust the speaker, setting the stage for Gaetz's move.

No U.S. House speaker has ever been removed from the position that puts the holder second in line in succession for the presidency after the vice president.