Donald Trump is concerned only about his reelection, Politico reported referring to White House ex-advisor John Bolton's interview with ABC.

"A lot of people have complained that he has a short attention span and he doesn't focus," Bolton said. "When it comes to reelection, his attention span is infinite. It's just too bad there wasn't more of that when it came to national security."

"I don't think he's fit for office, I don't think he has the competence to carry out the job. There really isn't any guiding principle that I was able to discern other than what's good for Donald Trump's reelection," Bolton noted.

"I hope [history] will remember [Trump] as a one-term president who didn't plunge the country irretrievably into a downward spiral we can't recall from. We can get over one term. I have absolute confidence — even if it's not the miracle of a conservative Republican being elected in November."

Bolton was fired from his post last September. His book 'The Room Where it Happened' is set to be published on June 23.