The Republican congressman George Santos has temporarily withdrawn from two House committees to which he was appointed by party leaders despite a spiraling scandal over his largely made-up résumé, bizarre past behavior and campaign finance filings.

Explaining his decision, Santos said he wanted to “focus on serving the constituents of New York’s third congressional district and providing federal level representation without distraction”.

Critics would argue Santos has provided plenty of distraction since winning his seat in November.

Earlier this month, the House speaker, Kevin McCarthy, appointed Santos to the committees on small business and science, space and technology.

The speaker did so despite confirming that a member of staff for Santos pretended to be McCarthy’s chief of staff while seeking campaign donations.

But that was hardly the biggest news of Santos’s first month in Congress.

Found to have largely fabricated his educational and professional résumé, Santos has denied or deflected reports about past conduct including an alleged fraud of a homeless veteran seeking medical care for his dog and appearances as a drag queen in Brazil, where he is also being investigated over alleged use of a stolen chequebook.

Santos is under local, state and federal investigation in the US. Last week it emerged that the congressman, who has also been known as Anthony Devolder, faces a criminal investigation by the Department of Justice over campaign finance filings that have prompted questions about the source of his wealth and a possible link to a Russian oligarch.

Santos’s district party and other New York Republicans have been joined by New York and national Democrats in calling for Santos to quit. Polling in the third district shows nearly 80% of voters there now think he should do so.

But if he did, prompting a special election, McCarthy would face further erosion of an already slender majority.

Before being sworn in, Santos backed McCarthy through 15 rounds of voting for speaker as the far right of the party rebelled. Since then, McCarthy and other party leaders have repeatedly said Santos should not resign.

Santos has admitted “embellishing” his résumé but repeatedly denied wrongdoing, bemoaned the tone of media coverage and said he will not step down.

News of his decision to step back from committee assignments came out of a closed-door party meeting on Capitol Hill on Tuesday morning.

Multiple news outlets cited an unnamed source as saying the New Yorker told fellow Republicans he had become “a distraction”.

McCarthy told reporters: “I met with George Santos yesterday and I think it was an appropriate decision that until he could clear everything up, he’s off committees right now … We had a discussion and he asked me if he could do that.”

In a statement, Santos’s office said: “He is recusing himself until he is cleared. Please note that his seat will be reserved until the congressman has been cleared of both campaign and personal financial investigations.”

In a subsequent personal statement, Santos said: “With the ongoing attention surrounding both my personal and campaign financial investigations, I have submitted a request to Speaker McCarthy that I be temporarily recused from my committee assignments until I am cleared.

“This was a decision that I take very seriously. The business of the 118th Congress must continue without media fanfare. It is important that I primarily focus on serving the constituents of New York’s third congressional district and providing federal level representation without distraction.”

Santos also thanked McCarthy “for meeting with me to discuss the matter and allowing me to take time to properly clear my name”.

Republicans greeted Santos’s withdrawals.

Marc Molinaro, another freshman from New York, told Politico: “The decision to not serve on committees is in his and our best interest. As I said, I think he should resign and focus on his defense. But I do welcome this decision.”

Don Bacon of Nebraska, a Republican moderate, told the same outlet Santos “apologised and said he was going to recuse himself … for now. He just said he recused himself for a while and then he’ll come back”.

Marjorie Taylor Greene of Georgia, both a leading rightwing extremist and a solid McCarthy ally, told reporters Santos “asked that we all support him when everything settles down for him to serve on committees”.

Pete Aguilar of California, the Democratic caucus chair, told reporters he was “struck by the chaos, confusion, dysfunction of the Republican conference.

“They defended putting him on committees and now they’re announcing that he’s not going to serve on a committee, so I don’t understand what the play of the day is. We have said from the beginning that George Santos is not fit to serve on any committees.”

Republicans, he said, were defending “someone who only has a passing relation to the truth”.

Among media responses to Santos’s withdrawal, Larry Sabato, director of the Center for Politics at the University of Virginia, plumped for satire.

“George Santos has stepped aside (with a push or two),” Sabato wrote. “… Is that any way to treat the founder of Walmart and the inventor of the iPhone?”