Chris Christie says Trump initially refused to prepare for the 2020 debates: 'I know how to do this. I'm already the president'

• Trump initially refused to prepare for the 2020 debates against Joe Biden, according to Chris Christie's new book.
• "What the fuck am I doing here?" Trump reportedly asked when he arrived at the first prep session.

Then-President Donald Trump initially refused to prepare for the 2020 presidential debates against his Democratic rival Joe Biden because he didn't think he needed to, according to a new book by former New Jersey Gov. Chris Christie.

Christie was the first 2016 Republican candidate to endorse Trump after dropping out, and he took on a leading role to prepare Trump for the 2020 debates. His book, "Republican Rescue: Saving the Party from Truth Deniers, Conspiracy Theorists, and the Dangerous Policies of Joe Biden," hit bookshelves on Tuesday.

"What the fuck am I doing here?" Trump reportedly asked when he walked into the first prep session in July 2020, which took place in a conference room at his New Jersey golf club. Christie joined other advisors, including former counselor to the president Kellyanne Conway and senior advisor Jared Kushner, for the session.

After Christie reminded Trump that they had to prepare for the first debate against Biden, Trump brushed it off and questioned why he had to practice in the first place.

"Yeah, but why am I doing this?" Trump asked, according to Christie's book.

"So you'll be ready for Biden," Christie replied.

Trump still resisted, saying, "I know how to do this. I'm already the president."

He said it again, and more emphatically. "I'm the president! I already know how to do this!"

Christie then urged Trump to reconsider his stance by handing him a stack of news reports and telling him that several incumbent presidents in recent history, from Ronald Reagan to Barack Obama, each lost their first debates when running for reelection.

"You, Mr. President, can make history by being the first incumbent president in the modern era to win the first debate," Christie told Trump.

The argument seemed to break through.

"Hmm. All right. I'll look at it," Trump said, and left the room with the papers, according to Christie's book.

Christie went on to write that although the first session was a "complete waste of time," Trump eventually agreed to participate in the prep sessions as long as they weren't called "mock debates."

"'If you need to do a mock debate, you're weak,' I remembered [Trump] telling me four years earlier,'" Christie wrote. "This might be more effective, I thought."

Trump's advisors ended up preparing him for the debates with lightning round-style questions in order to keep him focused and engaged, Christie wrote. But Trump's performance in the first debate against Biden still fell far short of what his team had hoped for.

Trump interrupted Biden or moderator Chris Wallace at least 128 times in the debate, prompting Biden to issue an exasperated plea: "Would you just shut up, man?"

In one of the most controversial moments of the night, Trump hesitated to condemn white supremacists and told the far-right extremist group Proud Boys to "stand back and stand by." Members of the group quickly seized on Trump's words and praised him in online forums.

CNN's Dana Bash called the debate a "shitshow," with other news anchors and pundits offering similar critiques. Trump's interruptions were so frequent that they prompted the Commission on Presidential Debates to issue new rules saying it would mute candidates' microphones to ensure they had the space to make their arguments.

Christie in his book described the 90-minute debate as a "disaster," "just awful," and "excruciating to sit through."

A spokesperson for Trump did not immediately respond to Insider's request for comment.