Several Senate Republicans said Tuesday that Environmental Protection Agency Administrator Scott Pruitt’s management and spending decisions should be subject to greater congressional scrutiny, although nearly all of them stopped short of asking him to resign.

The increasingly critical comments from Senate Republicans across the ideological spectrum — from longtime ally James M. Inhofe of Oklahoma to moderate Susan Collins of Maine — come as Pruitt readies for back-to-back appearances before two House committees Thursday in what promises to be a grilling from members of both parties. Pruitt has declined to coordinate with White House officials in preparing for the hearings, according to senior administration officials who spoke on the condition of anonymity to discuss internal deliberations.

Some GOP senators said Pruitt’s approach to spending taxpayer money and his private financial dealings — which has include the repeated use of first-class travel, an extensive security detail and a New York Times account of an unusual housing deal while he was serving as an Oklahoma state senator — have tarnished their party’s image and threaten to undermine President Trump’s avowed commitment to reform.

“Some of his behavior has hurt the president of the United States. He’s hurt the president’s credibility, he’s hurt the credibility of all of us, and it’d be way cooler if he would behave,” Sen. John Neely Kennedy (R-La.) told reporters Tuesday. “And I don’t mean to be too harsh, but you can’t just go around acting like a big shot, and you can’t go around seeing how close you can come to the line, and you can’t go around disrespecting taxpayer dollars. You can’t do it. You shouldn’t do it. And it shouldn’t be tolerated. That’s part of the swamp that we’re trying to clean up.”

Trump has been monitoring the recent coverage of Pruitt, according to aides, and has become increasingly concerned about the constant drumbeat of allegations against the EPA chief.

Several senators, including Senate Environment and Public Works Committee Chairman John Barrasso (R-Wyo.), said they were awaiting the results of an ongoing White House ethics review as well as his appearance before two House panels Thursday before determining next steps. Pruitt is slated to appear before the House Energy and Commerce Committee in the morning and before a House Appropriations subcommittee in the afternoon.

“I have questions about use of taxpayer dollars. I want to make sure taxpayers are getting value for their dollars, make sure money is being spent appropriately. So there continue to be serious questions,” Barrasso said. “We’ll see what comes out of the hearings on Thursday.”

Sen. Shelley Moore Capito (R-W.Va.), who sits on Environment and Public Works and has supported many of Pruitt’s policy initiatives, has asked to meet with the administrator this week before he testifies.

Inhofe, who used to chair the panel and supported Pruitt’s nomination, said he wants the committee to hold its own oversight hearing in the wake of the Times’s story this weekend.

“If some of the things were true, I’d have to look at that,” he said. “I’m checking out to see how authentic the accusations were. I don’t know that yet.”

Several senators said that although they were aware of the controversy swirling around Pruitt’s activities, they had not yet delved into the details. “It’s not in my committee’s jurisdiction,” said Sen. Ron Johnson (R-Wis.). “But let’s face it, what you hear is troubling.”

Collins remains the only Republican senator who has called on Pruitt to step down, suggesting his policy positions alone disqualify him from heading the EPA.

“The ethical allegations against him make it very difficult for the department to focus on its mission and are a distraction. They add to my concerns about his policy decisions,” she said.

But Collins, along with other Republicans, emphasized the decision to remove Pruitt lies with the president.

“Ultimately, it’s going to be a decision between the president and the administrator,” said South Dakota’s John Thune, who occupies the No. 3 position in the Senate GOP leadership. “But there’s enough smoke out there right now that it’s going to require some due diligence on the part of the White House, and  folks up here who are looking at it.”

Karoun Demirjian and Dino Grandoni contributed to this report.

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