In the new book, Battle for the Soul: Inside the Democrats’ Campaign to Defeat Trump, journalist Edward-Isaac Dovere claimed the former US President had some choice words to say about Mr Trump.
Mr Obama reportedly dubbed the Republican a “madman”, a “racist, sexist pig”, that “fu**ing lunatic” and a “corrupt motherf****r”.
According to Mr Dovere, the comments varied depending on what Mr Trump had done during his time as US President.
Mr Dovere wrote: “More often; ‘I didn’t think it would be this bad’.
“Sometimes; ‘I didn’t think we’d have a racist, sexist pig’.
“Depending on the outrage of the day… a passing, ‘that fu**ing lunatic’ with a shake of his head.”
The Atlantic journalist wrote Obama believed Mr Trump would be easy to knock off during the 2016 presidential race.
However, Mr Trump shocked the world when he beat former Secretary of State, US senator and first lady, Hillary Clinton.
And according to Mr Dovere, it was in 2017 when Mr Obama realised the Republican was a “madman”.
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“And that’s worth a lot.
“You’re not going to have to argue about them every day.
“It just won’t be so exhausting.”
Back in November last year, millions of Americans took to the polls to vote for the next President of the United States.
Mr Biden won more votes than any other candidate in American history.
But Mr Trump continued to claim voter fraud despite many Republicans distancing themselves from him.
Back in January, the former Republican president urged supporters to “walk down” to the Capitol building.
This sparked protests in Washington DC and Trump supporters broke into the Capitol building which forced Congress to evacuate.
A total of four people died during the riot, with one woman, Ashli Babbit, shot in the neck by police and three others dying in medical emergencies.
After being cleared of his second indictment, Mr Trump revealed he may stand in the 2024 election.
He said he may decide to beat the Democrats “for a third time”.
Speaking at the Conservative Political Action Conference (CPAC), Mr Trump said: “But who knows, I may even decide to beat them for a third time.”
Mr Trump continued: “I stand before you today to declare that the incredible journey we began together… there’s never been a journey so successful – we began it together four years ago and it is far from over.”
Battle for the Soul: Inside the Democrats’ Campaign to Defeat Trump will be released on May 25.
