A Republican lawmaker and former FBI agent told NPR on Sunday that it’s clear President Donald Trump was “manipulated” by Russian President Vladimir Putin.

“The President was manipulated by Vladimir Putin. … Vladimir Putin is a master manipulator,” Rep. Brian Fitzpatrick (R-PA) told NPR’s Michel Martin, adding that he was “frankly sickened by the exchange” between the two world leaders.

After appearing to publicly support Putin in his denial of meddling in the 2016 election, Trump attempted to walk back some of his comments, claiming he misspoke during a joint press conference with the Russian president. Many Republicans have responded with statements of fierce support of the U.S. intelligence community, but few have criticized Trump directly.

“It needs to be accepted as fact by everybody in our government because we need to respond to that reality and it’s a significant threat. We cannot let that happen again,” Fitzpatrick said.