Updated

The Republican leaders of the House and Senate announced Thursday that they will boycott the ObamaCare-created committee responsible for holding down Medicare costs, in a challenge to a controversial element of the health care overhaul.

The Individual Payment Advisory Board, or IPAB, has been described as a "death panel" by some of its fiercest critics. Though that epithet is not often used anymore to describe the panel, Republicans still say it would hurt seniors by forcing doctors to stop seeing patients.

House Speaker John Boehner and Senate Republican Leader Mitch McConnell, in a letter Thursday to President Obama, said they would refuse to recommend any nominees to the committee, reiterating that they think it should be repealed entirely.

They revived concerns that the panel would enforce Medicare cuts by reducing payments to providers and/or "eliminating" certain treatments.

"These reduced payments will force providers to stop seeing Medicare patients, the same way an increased number of doctors have stopped taking Medicaid patients. This will lead to access problems, waiting lists and denied care for seniors," they wrote.

The 15-member advisory board, known as IPAB, would have the power to force payment cuts on insurers, drug companies and other service providers if Medicare costs rise beyond certain levels.

The health care law explicitly forbids the board from rationing care, shifting costs to seniors or cutting their benefits. But Boehner, at a news conference Thursday, said the members still "have the authority to deny seniors access to care."

It's unclear what effect the boycott will have on the panel. The law says the president should consult with Congress on the nominations, but the president is free to make his own appointments. The members of the board, though, are supposed to be from both parties and nominees would be subject to Senate confirmation.

White House Press Secretary Jay Carney slammed Republicans for the stance and for renewed efforts to repeal the health care law.

"It just demonstrates again how out of touch with what the American people want the House Republicans have become. Instead of focusing on measures that could help us invest in innovation and manufacturing and job creation, instead of focusing on common-sense efforts to reduce our deficit in a balanced way, House Republicans are voting again to repeal the Affordable Care Act," Carney said.

Asked why the House was voting a 37th time to repeal all or part of the law, even though GOP leaders know the Democratic-controlled Senate will again ignore the vote, Boehner said there were about 70 new members of the House this year. "Frankly they have been asking for an opportunity to vote on it, and we are going to give it to them."

He said he supports total repeal of the law rather than efforts to amend it as it goes into effect over the next year.

Republicans say there have been only two previous votes to eliminate the health care law in its entirety. They say there have been more than 30 votes to partially repeal or defund the law, and several have been signed into law, including one eliminating an unpopular tax-filing requirement that would have affected millions of businesses.

Economists have predicted that the Medicare board's services might not be needed in the near future because Medicare cost increases appear to be manageable.

The Associated Press contributed to this report.