Former acting White House chief of staff Mick Mulvaney blasted former National Security Adviser John Bolton Thursday, telling "Special Report" that Bolton "at some point ... forgot that he was a staffer" in the Trump administration.

After host Bret Baier played a clip of his Tuesday interview with Bolton on the same program, Mulvaney -- now the U.S. special envoy for Northern Ireland -- claimed that Bolton had "forgot that he was the national security adviser and thought that he was most of the times, either the Secretary of State or the president.

"Every time I hear those clips [or] I see those interviews, it just makes me cringe as someone who was on the inner circle, thinking that this is someone going out publicly now and essentially just second-guessing the president in an attempt to prevent his reelection. It's a true betrayal of confidence."

TRUMP BLASTS BOLTON AS 'WASHED UP CREEPSTER' AS BOOK HITS SHELVES, SAYS HE SHOULD BE IN JAIL

In a "Hannity" town hall set to air later Thursday, Trump slammed Bolton as “crazy,” adding that “all he wants to do is bomb people.”

Bolton earlier this week defended his decision to write a tell-all book, "The Room Where It Happened," about his time in the Trump administration and denied violating record-keeping laws by destroying his notes while in the White House.

"John Bolton didn't like some of the president's decisions, didn't like some of the president's policies but instead of making an argument behind closed doors and then defending the positions publicly, John decided to sort of go off on his own and try and undermine the president," Mulvaney charged. "That's the cardinal sin of any staffer, but certainly [of] someone as high up in the hierarchy as the national security adviser."

Turning to the November election, Mulvaney downplayed polling showing the president consistently trailing presumptive Democratic presidential nominee Joe Biden and defended the president's "style" following reports that some Republican senators are calling for a "change of tone."

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"There are a lot of folks, Republicans included, who have never liked the president's style. What I say to those folks is that the president's style is probably one of the things that won him election in the first place in 2016," Mulvaney said. "And in any event, it's unlikely you're going to change his style."

"I think the better question, Bret, is how do you take the president's style and turn it into a huge advantage right now?" Mulvaney continued. "I think the thing that the campaign is not doing extraordinarily well is drawing those comparisons. They're trying to draw comparisons between Donald Trump and Joe Biden. But is it hard because Biden hasn't been out very much ... So the more they can draw those contrasts and make it Trump versus Biden as opposed to Trump versus Trump, I think the president will fare much better in that outcome."