Washington (CNN) -- Rep. Charlie Rangel temporarily stepped down as chairman of the House Ways and Means Committee on Wednesday, a decision forced by a growing storm of ethics controversies threatening the longtime congressman.





The 20-term New York Democrat told reporters he had submitted a letter to House Speaker Nancy Pelosi requesting a temporary leave of absence until a broad-reaching House ethics committee investigation concludes.





"In order to avoid my colleagues' having to defend me during their elections, I have this morning sent a letter to Speaker Pelosi asking her to grant me a leave of absence until such time as the ethics committee completes its work," Rangel said Wednesday.





In a statement, Pelosi said she had accepted Rangel's request and praised the congressman for "his decades of leadership on jobs, health care and the most significant economic issues of the day."





Read Rangel's letter to Pelosi





The night before Rangel said he had no plans to step aside from his powerful post. The Ways and Means Committee is responsible for drafting the nation's tax policies.





Rangel is being investigated for, among other things, failing to pay taxes on a home in the Dominican Republic. The congressman also has admitted failing to report several hundred thousand dollars in assets on federal disclosure forms.





In addition, he is under scrutiny for the purported misuse of a rent-controlled apartment for political purposes, as well as for allegedly preserving tax benefits for an oil-drilling company in exchange for donations to a project he supported at the City College of New York.





Rangel was formally admonished Friday by the House ethics committee for violating rules on receiving gifts. Specifically, the committee found that Rangel violated House gift rules by accepting reimbursement payments for travel to conferences in the Caribbean in 2007 and 2008.





Rangel's staff, according to the committee, knew that corporations had given money to the Carib News, which sponsored the events. That fact had not been divulged to the ethics committee when Rangel asked for and received approval to attend the trips, according to the committee's report. The committee found that while Rangel did not know about the contributions, he was nevertheless responsible.





A source told CNN on Tuesday that if Rangel stepped aside, senior Ways and Means Democrat Pete Stark would take over as the committee's chairman "on a temporary basis."





House Republicans plan to introduce a resolution Wednesday calling on Rangel to permanently step down and again force House Democrats to go on record defending him. They issued a statement after Rangel's announcement, calling his decision to temporarily step aside an "embarrassing episode" for the Democratic majority.





"Nancy Pelosi's promise to run the 'most ethical Congress in history' has been reduced to a punch line, and as a result she is presiding over a caucus in chaos," said GOP spokesman Ken Spain. "The Democrats -- under Speaker Pelosi's leadership -- are incapable of leading the United States Congress."





House Democrats have blocked previous GOP resolutions on the House floor, but several Democrats in competitive districts have come out publicly in recent days, saying they thought it was time for Rangel to step down.





Rangel is a founding member of the Congressional Black Caucus, which has 42 members in the House.





CNN's Brianna Keilar and Deirdre Walsh contributed to this report
What committees was Rangel on? What is Rangel being investigated for? What Republicans plan? Who is responsible for drafting nation's tax policies? Who is being called to step aside? What gifts did Rangel recieve?
House Ways and Means failing to pay taxes on a home in the Dominican Republic. introduce a resolution The Ways and Means Committee Rep. Charlie Rangel reimbursement payments for travel to conferences in the Caribbean
question: What committees was Rangel on?, answer: House Ways and Means | question: What is Rangel being investigated for?, answer: failing to pay taxes on a home in the Dominican Republic. | question: What Republicans plan?, answer: introduce a resolution | question: Who is responsible for drafting nation's tax policies?, answer: The Ways and Means Committee | question: Who is being called to step aside?, answer: Rep. Charlie Rangel | question: What gifts did Rangel recieve?, answer: reimbursement payments for travel to conferences in the Caribbean