Washington (CNN) Environmental Protection Agency Administrator Scott Pruitt said Tuesday that he has no recollection of stinging remarks he made back in 2016 when he argued that Donald Trump would use executive power "in a way that is truly unconstitutional" and would be "more abusive" to the Constitution than President Barack Obama.

"I believe that Donald Trump in the White House will be more abusive to the Constitution than Barack Obama and that's saying a lot," Pruitt said during a February 4, 2016, interview on Tulsa radio station KFAQ.

His remarks were first uncovered by the watchdog group Documented

When asked during the 2016 interview if he was a Trump supporter, Pruitt answered no. At the time, Pruitt was serving as Oklahoma attorney general and "National Chairman of Federal-State Relations" for Republican candidate Jeb Bush's campaign before Bush dropped out later that month.

"If Donald Trump is the nominee and eventually the President, he would take, I think, unapologetic steps to use executive power to confront Congress in a way that is truly unconstitutional," said Pruitt, who was tapped by Trump to lead the EPA in December 2016.

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