(Adds Warner and Haspel comments)
WASHINGTON, Jan 29 (Reuters) - U.S. congressional Democrats said on Tuesday they are not satisfied with the Trump administration's decision to ease sanctions on companies linked to Russian oligarch Oleg Deripaska, demanding briefings and planning legislation.
The leaders of four House of Representatives committees said they were considering legislation to ensure Russian aluminum giant Rusal and its parent En+ comply with the agreement that allowed them to be removed from a U.S. sanctions list.
"We are considering additional legislative actions to ensure that (the U.S.) Treasury and these companies comply with the agreement in letter and in spirit," the four Democratic chairs of the House Ways and Means, Foreign Affairs, Intelligence and Financial Services committees said in a joint statement.
And Senator Mark Warner, the top Democrat on the Senate Intelligence Committee, wrote to Treasury Secretary Steven Mnuchin to request ongoing briefings from the administration on the deal it reached to ease sanctions on the companies.
Warner said he was concerned that the administration had not disclosed every detail of its agreement with Deripaska, and that Deripaska will continue to control the companies.
The U.S. Treasury Department said on Sunday that it was lifting sanctions imposed on aluminum firm US Rusal Plc, En+ Group plc and JSC EuroSibEnergo, three companies linked to the billionaire Deripaska, an influential businessman close to Russian President Vladimir Putin.
Treasury had announced on Dec. 20 that the sanctions would be lifted, watering down the toughest penalties imposed since Moscow's 2014 annexation of Crimea.
But the Democratic lawmakers complained that the sanctions were lifted before a congressional review could be completed.
"Mr. Deripaska has a history of involvement with Moscow for malign purposes, and we have serious questions about whether the agreement reached between Treasury and Mr. Deripaska," the lawmakers said in a statement.
The House statement was released by Ways and Means Committee Chairman Richard Neal, House Foreign Affairs Committee Chairman Eliot Engel, House Permanent Select Committee on Intelligence Chairman Adam Schiff, and House Financial Services Committee Chairwoman Maxine Waters. All are Democrats.
Separately, Republican Senator Susan Collins asked CIA Director Gina Haspel during a Senate Intelligence Committee hearing on Tuesday whether the CIA had expressed concern about the decision to lift the sanctions.
Haspel said it had not.
Collins was one of about a dozen Senate Republicans who broke from party leaders and Trump to support a failed Democratic-led resolution that sought to keep the sanctions in place. (Reporting by Tim Ahmann and Diane Bartz, additional reporting by Patricia Zengerle; editing by G Crosse and Lisa Shumaker)