WASHINGTON >> Republican and Democratic senators clashed today over changes the Republicans made to their sweeping tax legislation late Tuesday night, as the momentum behind the tax overhaul showed no signs of slowing with votes expected in both chambers of Congress later this week.

Democrats attacked Republicans for inserting a repeal of the health care law’s requirement that most people have health insurance into the tax bill and for imposing a 2025 expiration date for individual tax cuts, while making the corporate tax cuts permanent.

“This bill seems to get worse by the hour,” said Sen. Ron Wyden of Oregon, the ranking Democrat on the Senate Finance Committee. “This is not just another garden variety attack on the Affordable Care Act, this is a repeal of that law.”

Repealing the health law’s individual mandate allows Republicans to save more than $300 billion over 10 years. According to the Congressional Budget Office, 13 million fewer people would be insured after a decade without the mandate and health insurance premiums would rise by about 10 percent.

Sen. Orrin Hatch, R-Utah, chairman of the finance committee, downplayed the move to make the individual tax cuts temporary, not mentioning that change in an opening statement in which he defended his party’s right to undo the mandate. He later suggested that Republicans would be unlikely to resist if Democrats wanted to help them make the cuts permanent after they expire.

“We’ll hear claims that the inclusion of the individual mandate tax relief is some kind of process foul and that we’ve somehow expanded the scope of the markup by including it in the modification,” Hatch said. “As we reiterated several times yesterday, the individual mandate is a tax.”

Hatch and Wyden raised their voices and spoke over each other as they clashed over the injection of health care into the tax debate, with Hatch at one point demanding that his leadership of the committee be respected.

“Let me be in charge of this committee, not you,” Hatch said.

The third day of debate over the tax bill in the Senate Finance Committee comes before an expected vote by the panel Friday. The full Senate is expected to vote on the bill after Thanksgiving while the full House is expected to vote on its bill Thursday.

Another Senate panel, the Energy and Natural Resources Committee, voted Wednesday to approve legislation that would open the Arctic National Wildlife Refuge in Alaska to oil and gas drilling.

That legislation is to be merged with the tax bill, which Republicans are planning to pass using special procedures that protect against a Democratic filibuster in the Senate. Under that strategy, the drilling measure would share the protection from a filibuster.

Allowing drilling in the wildlife refuge, known as ANWR, is a longtime goal of the energy committee’s chairwoman, Sen. Lisa Murkowski, R-Alaska.

This summer, Murkowski was among the Republicans to vote against repealing the health care law, making her a closely watched figure as the Senate plunges back into a debate over health care.

Asked today about the repeal of the individual mandate, she showed no eagerness to discuss the subject. “My whole focus this week, you’re going to be shocked to know, has been ANWR,” she said.

With President Donald Trump having returned from Asia on Tuesday night, the administration has been actively pressing members of Congress to put any differences aside and get behind the bill.

Big rifts remain between the House and Senate tax bills, with the Senate’s repeal of the state and local tax deduction and the mandate being among the most significant differences.

House Speaker Paul Ryan, R-Wis., said on CNBC this morning that the House is not yet prepared to make changes on its legislation to accommodate the Senate in those areas.

“Of course we don’t like the individual mandate,” Ryan said. “But right now we’re just purely focused on tax reform from the tax code side.”

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