Then-President-elect Donald Trump is said to have asked outgoing President Barack Obama in 2017 what he thought his biggest mistake was as they traveled from the White House to the Capitol building, according to a new book.

“Peril,” by Bob Woodward and Robert Costa, offers a political insight into the months before and after the 2020 election, including the COVID-19 pandemic, the Jan. 6 riot and the 2020 presidential campaign.

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As it covers the inauguration of President Biden, the book reports that the Trump experience of that day – when he took off in Marine One to Mar-a-Lago ahead of the ceremony – was “full circle” from his own inauguration in 2017.

Woodward and Costa report that Trump and Obama rode from the White House to the Capitol, along with Sen. Roy Blunt, who was responsible for planning the inaugural ceremony.

“What was your biggest mistake?” asked the president-elect to his predecessor.

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Obama is then said to have paused and looked back at Trump.

“I can’t think of anything,” he is reported to have responded.

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Trump then changed the subject, and asked, “Is this the car you use all the time?”

The book has already made headlines, in part for its reporting about how General Mark Milley was in communication with the Chinese to reassure them about fears of an attack during the chaos surrounding the Jan. 6 Capitol riot.