President Trump took to Twitter on Saturday morning to defend his mental health, as an explosive new tell-all book portraying Trump as unfit for the presidency sold out from coast to coast after going on sale on Friday.

The publisher, Henry Holt, is rushing to print more copies of “Fire and Fury: Inside the Trump White House” by journalist Michael Wolff. The book has been number one on the Amazon best-sellers list since Wednesday, when excerpts of the book were published online. In these excerpts, former White House chief strategist Steve Bannon is quoted portraying his former boss as wholly unprepared for the presidency, accusing Donald Trump Jr. of “treason,” and predicting Robert Mueller’s Russia investigation will find evidence of money laundering.

Bannon has since tried to walk back his comments, claiming his treason comments were a reference to Trump’s former campaign manager Paul Manafort, not Trump’s son, Donald Trump Jr. Bannon also says he has unwavering support for the president. Late last week, President Trump tried frantically and unsuccessfully to stop the publication of the book, with his lawyers sending cease and desist letters to Bannon, author Michael Wolff and publisher Henry Holt.

But after failing to stop the book’s publication and distribution, President Trump took to Twitter to try to defend his mental health, tweeting, “I went from VERY successful businessman, to top T.V. Star, to President of the United States (on my first try). I think that would qualify as not smart, but genius....and a very stable genius at that!”

Those were President Trump’s tweets from 7:20 a.m. Saturday morning, while he was at Camp David to meet with lawmakers about national policy issues, including the budget and healthcare. He tweeted this only 10 minutes after a segment on “Fox & Friends” covered the media’s increasing questions about Trump’s mental health. On Saturday morning, Trump also said he wished the U.S. had stronger libel laws. Trump has also lashed out at the book’s author, Michael Wolff, calling him a “total loser.” This is Wolff, speaking on NBC’s “Meet the Press” on Sunday.

Michael Wolff: “If I left out anything, it’s probably stuff that was even more damning.”

Chuck Todd: “It’s that bad.”

Michael Wolff: “It’s that bad. I mean, it’s an extraordinary moment in time. And the last several days focused on my book, I think, are proof of this. This is—what happened here? What’s going on here? This is, you know, I think, not an exaggeration and not unreasonable, and it’s not unreasonable to say this is 25th Amendment kind of stuff.”