The author who lifted the lid on Donald Trump's chaotic presidency says there's no way he will run for a second term – even if he manages to survive his first.

Author Michael Wolff told Newstalk ZB's Mike Hosking today that he agreed with former Trump adviser Steve Bannon – that Trump would either be impeached, would quit – or would limp to the end of a first term and not seek a second.

"A zero per cent chance that he gets another term or runs again," Wolff told Hosking.

READ MORE: Trump next in line for Russia questioning, could he be impeached?

Wolff insists he did not set out to write a critical account of the presidency, though now concedes he had no idea what he was getting in to.

"Clearly this book has touched a nerve, a nerve in the US and around the world. And I think it goes to the nature of Donald Trump - it is so hard to understand this guy, what he is, what he wants, where he will take us, why he finds himself in the position that he finds himself.

"The hunger to understand this has clearly been one of the things that has propelled my book."

Wolff was allowed access to the White House and conducted more than 200 interviews for the book.

Trump has responded with legal threats, including a claim that his privacy has been breached.

Wolff told Hosking the threats were "preposterous".

"It would be almost impossible to invade the privacy of the president of the US."

Wolff insisted that he started the book with an open mind: "I had no assumptions about what I would find".

"I was perfectly willing to walk into this White House and discover that Donald Trump had a plan and that he might well be a successful president. In fact I discovered quite the opposite - he certainly had no plan and the chances for him to be a successful president I would rate as nil."

The author said he uncovered a White House where "literally nobody knows what they're doing".

"Donald Trump does not know what he's doing. Donald Trump I don't think particularly cares about what he's doing," Wolff said.

"Donald Trump is someone who is concerned almost exclusively with his own gratification – that creates the chaos, the immorality, the whatever is illegal. And it ultimately means that no one is capable of thinking in ways that are larger than themselves."

Asked by Hosking what Trump's prospects were, Wolff said he agreed with Bannon's numbers: a 33 per cent chance Trump would be impeached, 33 per cent chance he'd quit, or a 33 per cent chance he "limps" to the end of the first term.

"I think that there is no possibility of a second term," Wolff said.

"This is an aberrant president, an aberrant presidency."

But despite writing a searing book outlining the administration's failings, Wolff said he actually found Trump "very likeable".

"He heaps praise and flattery on you, so much praise and flattery that you feel a little sheepish about the whole thing".

However, the repeated flattery ended up making you feel "there's something odd here to say the least".

Wolff told Hosking he believed there would be "many" books written about Trump.

"He is the story of our time."

Wolff's book, Fire and Fury: Inside the Trump White House, has already sold millions of copies worldwide.

LISTEN ABOVE AS MICHAEL WOLFF SPEAKS WITH MIKE HOSKING