A historian admired by Liz Truss has claimed she has misunderstood his work to a “mind-blowing” degree, prompting him to feel “terribly guilty”.

The Prime Minister previously told The Times “anything” by Rick Perlstein charted among her favourite books, specifically his writing on former US presidents Richard Nixon and Ronald Reagan.

But the historian claimed she had missed what he thought was obvious cynicism in his book The Invisible Bridge, covering the fall of Mr Nixon and rise of Mr Reagan.

Mr Perlstein told Times Radio the work was inspired by what he presumed was “transparently and self-evidently a moral and political critique of the notion that you should bamboozle the public”.

The title is a reference to a piece of advice to Mr Nixon attributed to former Soviet leader Nikita Khrushchev: “If the people believe there’s an imaginary river out there, you don’t tell them there’s no river there.

“You build an imaginary bridge over the imaginary river.”

Mr Perlstein said that, during her leadership campaign, one of Ms Truss’s aides was “kind of peddling this quote” as an example of why she should win, as she “understood what Reagan understood: that you’re supposed to bamboozle the public”.

“She didn’t grasp, apparently, that it was cynicism,” he said.

“The idea that someone would come across the account that I offer of the cynicism, intellectual vacuity, and just basic emptiness of the promises that were made by Ronald Reagan in this regard, and say, ‘Jolly good, this is what I’m going to try for England’, is kind of mind-blowing.

“America is bad off with Trump, but this is a terrible situation for England that they would endorse a leader like this.”

Mr Perlstein said the theme of the book was that Mr Reagan “basically created this fantasy about how to create a prosperous and dynamic society, one of the tenets of which was this fantasy about lowering taxes on the rich, creating prosperity for everyone”.

“I feel terribly, terribly guilty,” he said.

“I did my best to explain that the ideas that she’s proposing… were terrible for the United States.

“I didn’t quite grasp how if another country that didn’t have America’s advantages of having the reserve currency of the world would adapt it, it would be in many ways 10 times worse. It’s been a very curious experience for me.”