Story highlights Pruitt called Trump an "empty vessel" on the Constitution and rule of law in a February 2016 interview with a local Oklahoma radio show

Earlier last week, Democratic Sen. Sheldon Whitehouse asked Pruitt about comments about Trup he made on a different radio show

(CNN) Environmental Protection Agency administrator Scott Pruitt called Donald Trump an "empty vessel" on the Constitution and rule of law in a February 2016 interview with a local Oklahoma radio show.

The previously unreported remarks are the second known instance that Pruitt harshly criticized Trump during the 2016 presidential campaign.

"I think he's an empty vessel when it comes to things like the Constitution and rule of law," Pruitt said on the "Exploring Energy" radio show on February 11. "I'm very concerned that perhaps if he's in the White House, that there may be a very blunt instrument as the voice of the Constitution."

"This President, the one we have there now, has at least tried to nuance his unlawfulness," Pruitt continued, discussing then-President Barack Obama. "He at least sits back and says, 'How do we break the law and so where it's really tough to show that we have?' I'm not sure that Donald Trump would."

Earlier last week, Democratic Sen. Sheldon Whitehouse asked Pruitt about comments he made on a different local Oklahoma radio show on February 4, 2016, where he said then-candidate Trump would be more abusive to the Constitution than Obama. Pruitt said he didn't recall those remarks nor did they reflect his current views on the President.

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