Donald Trump mocked yet again, This time by an author

Author of the book 'Fire and Fury: Inside the Trump White House' Michael Wolff has hit back at United States President Donald Trump, stressing his credibility was being questioned by a man who has "less credibility than anyone who walks on Earth."

President Trump had purported that he gave Wolff "zero access" to the White House for the book.

"I absolutely spoke to the president. It certainly was not off the record," the Hill, quoted Wolff, as saying on NBC's 'Today Show.'

"My window into Donald Trump is pretty significant. I work like every journalist works. I have recordings. I have notes. I am certainly and absolutely in every way comfortable with what I have reported," he added.

Earlier on Thursday, Trump had lambasted Wolff's book on Twitter.

"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!" Trump, wrote, in a Twitter post.