President Donald Trump this week accused Barack Obama of “spying” on his 2016 campaign and called his predecessor’s alleged actions “treasonous.”

“What they did was treasonous, Okay? It was treasonous,” Trump told conservative author and commentator Doug Wead for his forthcoming book, Inside Trump’s White House: The Real Story of His Presidency, according to The Washington Examiner. 

“The interesting thing out of all of this is that we caught them spying on the election. They were spying on my campaign. So you know? What is that all about?” said Trump.

Trump’s latest comments follow his similar unsubstantiated claim about Obama from 2017. At the time, Trump falsely alleged the former Democratic president “had my wires tapped” in Trump Tower due to concerns that his campaign had colluded with Russia during the 2016 election. Trump later claimed he simply intended to express how he felt and that he did not truly believe Obama’s administration had been spying on him.

“Just found out that Obama had my ‘wires tapped’ in Trump Tower just before the victory. Nothing found. This is McCarthyism!” Trump tweeted in March 2017.

Earlier this year, Attorney General William Barr said without evidence that the FBI may have spied on Trump’s campaign team in 2016.

“I think spying did occur,” Barr told a congressional committee in April.

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In excerpts of Wead’s upcoming book provided to the Examiner, Trump boasted to the author that he was correct regarding his theory about Obama’s administration spying on him.

“It turned out I was right. By the way,” Trump said. “In fact, what I said was peanuts compared to what they did. They were spying on my campaign. They got caught and they said, ‘Oh we were not spying. It was actually an investigation.’ Can you imagine an administration investigating its political opponents?”

Trump’s reiteration of his previous comments about Obama come as he continues to be the subject of an impeachment inquiry from House Democrats for his attempts to solicit help from foreign governments to investigate Joe Biden and other political opponents.

Wead’s publisher says his new book — which is set to be released on Nov. 26 — includes interviews with the president’s three eldest children — Ivanka Trump, Donald Trump Jr. and Eric Trump. It also contains interviews with his senior adviser Jared Kushner, acting White House Chief of Staff Mick Mulvaney and Eric Trump’s wife Lara Trump.