The Democratic leaders of seven House panels are demanding Treasury Secretary Steven Mnuchin delay implementing a planned easing of sanctions on businesses tied to a prominent Russian oligarch until the Treasury Department briefs committee members on the matter.

The committee chairs told Mnuchin they want the briefing to take place before Friday, as they are working against the clock if they want to stop the administration from acting on its mid-December announcement that it would roll back sanctions.

“There are a number of additional questions that we and other Members of Congress must pursue to fully assess whether the U.S. agreement and the sanctions terminations are justified,” the panel chairs wrote, complaining that the administration had intentionally announced the change in policy right before a holiday and a government shutdown, making it difficult for members to exercise their right to challenge the decision.

The Democratic leaders expressed particular alarm about the proposed easement of sanctions because of the oligarch who would benefit from the change: Oleg Deripaska, who has ties to former Trump campaign chairman Paul Manafort, and “who has abetted the Putin Regime’s malign activity against the United States,” the lawmakers wrote.

They asked for the Treasury Department to engage in “a full discussion of all aspects of the agreement” the administration reached with Derispaska, “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.”

In 2017, Congress gave itself the authority to prevent the president from reducing any Russia-related sanctions, but only if lawmakers voted to do so within a 30-day window of the administration announcing its intentions. The Trump administration announced it would lift the sanctions on the businesses in question on Dec. 19.