The Central Intelligence Agency (CIA) says it didn't raise any concerns over the lifting of sanctions by the U.S. Treasury Department on three companies linked to Russian oligarch Oleg Deripaska.

CIA Director Gina Haspel told a Senate hearing on January 29 that the agency only provided information about Deripaska to the Treasury as it deliberated on what to do.

"No, I don't believe we raised any concerns but we provided all the supportive intelligence," Haspel told the hearing.

The Treasury said the removal of sanctions was based on the fact that aluminum giant Rusal, its parent company En+, and power firm EuroSibEnergo "have reduced Oleg Deripaska's direct and indirect shareholding stake in these companies and severed his control."

The sanctions were initially imposed in April, but they roiled global metals markets, unnerving businesses in the United States and Europe; Rusal is one of the world's largest aluminum producers.

The U.S. administration later reached a deal with the Russian firms to end Deripaska's control in return for a lifting of sanctions.

Four top U.S. lawmakers in the House said on January 29 that they were considering legislation to ensure aluminum giant Rusal and its parent En+ comply with the agreement.

Deripaska, who is widely believed to have close ties to the Kremlin, agreed to dispose of his controlling stakes in the companies. He himself remains subject to U.S. sanctions.

Deripaska has reduced his stake in En+ to 44.95 percent from about 70 percent previously, to comply with the lifting of the sanctions.

"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.

U.S. critics have accused President Donald Trump of making too many concessions to Russia for nothing in return, while Trump has insisted he has been tougher on Moscow than previous presidents.

Many Democratic lawmakers, and even some Republicans, insist that it was inappropriate to ease the sanctions at a time while Special Counsel Robert Mueller is probing whether Trump's 2016 presidential campaign colluded with Moscow.

With reporting by Reuters and AP