• According to a new book on the Trump administration, former White House chief of staff said the most important advice he gave to the president was not to tweet.
• “No. Don’t tweet that. No,” Kelly said in the book, according to Axios. “Don’t change your policy on that. No, no, no.”
• ABC chief Washington correspondent Jonathan Karl reportedly notes in his book that Kelly “agreed to allow me to quote this and other previously off-the-record remarks he made while he was chief of staff.”
• Visit Business Insider’s homepage for more stories.

Former White House Chief of Staff John Kelly is allowing the disclosure of some of the inner workings of the Trump administration in an upcoming book by ABC chief Washington correspondent Jonathan Karl, including the “most important” action he took for President Donald Trump.

According to an Axios report, Karl’s upcoming book, “Front Row at the Trump Show,” details how Kelly directed the traffic for the White House staff and regulated the president’s Twitter feed. Kelly recalled in the book that the most important piece of advice he gave to Trump was not to tweet.

“No. Don’t tweet that. No,” Kelly said in the book, according to Axios. “Don’t change your policy on that. No, no, no.”

Trump selected Kelly after then-Chief of Staff Reince Priebus was ousted in July 2017. As a former Marine Corps general, Kelly was long viewed as a choice to bring order to what had been a chaotic West Wing.

Upon his arrival, Kelly drastically limited the White House staff’s unfettered access to Trump, a move that reportedly included members of the president’s own family – his son-in-law and senior adviser, Jared Kushner, and his daughter and senior adviser, Ivanka Trump.

Karl notes in the book that Kelly “agreed to allow me to quote this and other previously off-the-record remarks he made while he was chief of staff,” a move that other Marine Corps generals previously on Trump’s staff, including former Defence Secretary James Mattis, declined to do out of respect for the office of the presidency.

Kelly attempted to regulate Trump’s discussions, including phone calls with world leaders, to prevent broaching sensitive information, according to news reports. Trump frequently delivers his musings to the world via tweet, often before federal agencies can announce their own official statements.

Kelly was unceremoniously fired in December 2018, months after his relationship with the president reportedly grew sour. Trump went on to disparage Kelly’s tenure after the former general publicly criticised the president’s policies and demeanour.

“When I terminated John Kelly, which I couldn’t do fast enough, he knew full well that he was way over his head,” Trump tweeted in February. “Being Chief of Staff just wasn’t for him. He came in with a bang, went out with a whimper, but like so many X’s, he misses the action & just can’t keep his mouth shut.”

Karl’s book is available on March 31.

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