Irish bookstores say demand is already extremely strong for a tell-all expose on Donald Trump which isn't released here until Tuesday.

Fire and Fury is now on sale in the US, four days earlier than scheduled, despite the President's lawyers trying to block it by issuing a cease and desist letter threatening libel action.

The book contains a number of explosive claims about the administration but Donald Trump has dismissed it as full of lies.

Nicole Gernon reports:

It's based heavily on conversations with former strategist, Steve Bannon, which include him describing the meeting between the president’s son and a group of Russians as treasonous

Donald Trump says he authorised zero access to the White House to the author Michael Wolff for what he calls a 'phony book'.

I authorized Zero access to White House (actually turned him down many times) for author of phony book! I never spoke to him for book. Full of lies, misrepresentations and sources that don’t exist. Look at this guy’s past and watch what happens to him and Sloppy Steve!

— Donald J. Trump (@realDonaldTrump) January 5, 2018

He also dismissed Steve Bannon's involvement saying "when he lost his job, he also lost his mind"

There are claims that Trump only entered the presidential race to boost his brand, that he never expected to win and that he sleeps in a separate bedroom to his wife.

Another suggests campaign aide Sam Nunberg tried to explain the Constitution to Mr. Trump but only got as far as the Fourth Amendment, before he became bored and "his eyes (were) rolling back in his head".

Bookstores here say they're experiencing strong demand for the book which isn't available here until Tuesday, but for those who can't wait it's available on Kindle now.