WASHINGTON (AP) — The leaders of seven House committees are calling on Treasury Secretary Steven Mnuchin to explain why the United States is easing sanctions on companies linked to Russian oligarch Oleg Deripaska. It’s one of the first moves of the new Democratic House to scrutinize President Donald Trump’s actions related to Russia.

The Democrats wrote to Mnuchin on Tuesday to ask about a December announcement that the U.S. would lift sanctions on the aluminum manufacturing giant Rusal and two other companies connected to Deripaska. Mnuchin said then that Deripaska would remain blacklisted as part of sanctions that targeted tycoons close to the Kremlin, but that the companies had committed to “significantly diminish Deripaska’s ownership and sever his control.”

In a letter to Mnuchin, the Democrats say the deal appears to allow Deripaska to keep “significant ownership” of one of the companies.

“As the chairs of committees with oversight jurisdiction over the U.S. response to Russia’s attempts to interfere in our elections and other hostile actions, we have a number of concerns about the agreement that the U.S. has reached with Mr. Deripaska,” the Democrats wrote.

They asked Mnuchin to delay implementation of the sanctions termination until he has fully briefed members of Congress about “all aspects of the agreement, the sanctions termination, and the impact that these decisions would have on the U.S. effort to end Russia’s malign activities aimed at our country.”

The Democrats gave Mnuchin until the end of the day Friday to respond.

The Treasury Department said it intends to provide the briefing and will do so as soon as possible.

Congress has 30 days to block the move to terminate the sanctions, but the lawmakers said that review was difficult because of the timing. Treasury announced the move just before the December recess and before the start of the government shutdown.

In addition to Rusal, Treasury officials said, sanctions against EN+ Group, the holding company that owns nearly 50 percent of Rusal, and Russian power company JSC EuroSibEnergo would also be lifted.

The announcement that the sanctions would be lifted followed a lobbying campaign paid for by the chairman of EN+’s board, Gregory Barker, a conservative member of Britain’s House of Lords, to convince the Trump administration to lift the sanctions against the companies.

Barker, a former British energy minister, hired the U.S. firm Mercury LLC in May to support his efforts to negotiate Deripaska’s exit from the EN+ board and “the reduction of his ownership interest in the company.”

The letter to Mnuchin was signed by House Ways and Means Chairman Richard Neal, D-Mass.; House Financial Services Chairwoman Maxine Waters, D-Calif.; House Foreign Affairs Committee Chairman Eliot Engel, D-N.Y.; House Intelligence Committee Chairman Adam Schiff, D-Calif.; House Oversight and Reform Committee Chairman Elijah Cummings, D-Md.; House Judiciary Committee Chairman Jerrold Nadler, D-N.Y.; and House Homeland Security Committee Chairman Bennie Thompson, D-Miss.