WASHINGTON — The Republican chairman of the Senate Environment Committee voiced support Monday for Environmental Protection Agency chief Scott Pruitt, even as other Republicans expressed concern about Pruitt’s ethics and spending on security and travel.

Sen. John Barrasso of Wyoming said Pruitt has accomplished key priorities as EPA head, mainly in reversing “punishing regulations” imposed under President Barack Obama. Barrasso said he saw the positive impact of Pruitt’s actions late last month as he and Pruitt toured a Wyoming coal mine.

Barrasso acknowledged that “certain questions have been raised about internal operations” at EPA and Pruitt’s actions, but said he will wait for a White House review before reaching a judgment.

Three Republican senators criticized Pruitt on Sunday amid expanded ethics investigations of his spending and possible perks he’s received.

Sen. John Kennedy, R-La., called Pruitt’s behavior stupid and “juvenile” and urged him to “stop acting like a chucklehead, stop the unforced errors, stop leading with your chin. If you don’t need to fly first class, don’t. Don’t turn on the siren on your SUV just to watch people move over. You represent the president of the United States.”

“Ethics matter. Impropriety matters. The appearance of impropriety matters,” Kennedy told CBS’ “Face the Nation,” adding that Pruitt’s actions were “distracting from the business that we’re trying to do for the American people.”

The Republican-led House Oversight committee confirmed Monday it has expanded its review of Pruitt’s travel spending to address questions surrounding his bargain $50-a-night rental of a Capitol Hill condominium tied to a fossil fuels lobbyist.

The Office of Government Ethics also has issued a letter to EPA demanding documents related to the condo rental. And it reports that at least five agency officials faced retaliation after questioning Pruitt’s outsized spending for travel, unprecedented security precautions and pricey office furniture.

President Donald Trump defended Pruitt in a tweet over the weekend, saying the EPA chief is “doing a great job” and downplaying the ethical questions. Trump called Pruitt’s security spending “somewhat more” than Pruitt’s predecessor and said Pruitt had received death threats “because of his bold actions at EPA.”

The Associated Press reported Friday that the 20-member team tasked with providing day-and-night protection for Pruitt had racked up salary, overtime and travel expenses approaching $3 million.

Sen. Lindsey Graham, R-S.C, said Pruitt has “done a good job, but I’m looking to see what the oversight committee is going to say.”

Graham called the $50-a-night condo rental troubling, adding that most people could not get a room for $50 a night in Washington.

“The bottom line, this doesn’t look good,” Graham said on ABC’s “This Week.”

Sen. Susan Collins, R-Maine, called Pruitt “the wrong person to head the EPA” and said, “This daily drip of accusations of excessive spending and ethical violations serve to further distract the agency from accomplishing its very important mission.”

Collins, the lone Republican to vote against Pruitt’s confirmation last year, spoke on CNN’s “State of the Union.”

Meanwhile, Democratic Sen. Jeff Merkley of Oregon called on Pruitt to resign, while Sen. Tammy Duckworth, D-Ill., requested a watchdog investigation of salary increases given to two top Pruitt aides. The EPA’s inspector general has opened an audit into whether Pruitt improperly used authority granted under the Safe Drinking Water Act to provide the raises to two of his closest aides. Pruitt denied knowing about the raises in a media interview last week, even though the statutory authority under which the raises were granted requires his approval.

Duckworth asked the Government Accountability Office to “bring clarity and understanding to these potential violations of federal law.”

Merkley said Monday that Pruitt “plays fast and loose with propriety” in serving the oil and gas industry and said, “the flood of revelations in the last few weeks makes clear that he is consumed by self-aggrandizement and that he is abusing his position in order to serve himself, not the American people.”

If Pruitt won’t resign, Trump should fire him immediately, Merkley said.