(Bloomberg) -- Former Secretary of State Rex Tillerson and former White House Chief of Staff John Kelly tried to undermine Donald Trump’s decisions because they said the president didn’t know what he was doing, former U.S. ambassador Nikki Haley said in excerpts of a new book.

“Kelly and Tillerson confided in me that when they resisted the president, they weren’t being insubordinate, they were trying to save the country,” Haley said, according to the Washington Post.

“It was their decisions, not the president’s, that were in the best interests of America, they said. The president didn’t know what he was doing,” Haley wrote. She said Tillerson and Kelly tried to enlist her in their effort to work around Trump, but she refused.

Tillerson was “exhausting” and imperious, and Kelly was suspicious of her access to the president, Haley, a former South Carolina governor who quit the Trump administration last year, wrote in “With All Due Respect,” due to be published Tuesday.

The Post said Tillerson didn’t respond to a request for comment. Kelly said that if providing the president “with the best and most open, legal and ethical staffing advice from across the [government] so he could make an informed decision is ‘working against Trump,’ then guilty as charged.”

Haley, in an interview on Sunday with CBS News, said she told Tillerson and Kelly they should be talking to the president about their disagreements, not “asking me to join them in their sidebar plan” to thwart his policies.

“To undermine a president is really a very dangerous thing,” Haley, who served as ambassador to the United Nations, told CBS. “And it goes against the Constitution, and it goes against what the American people want. And it was offensive.”

Putin, Charlottesville

Haley wrote about two disagreements she had with Trump while in his cabinet. She said she went privately to him with her concern that he had ceded authority to Russian President Vladi­mir Putin after the two leaders met in Helsinki in 2017, and objected to what she called Trump’s “moral equivalence” in response to a white supremacist march in Charlottesville, Virginia, that summer that left a protester dead.

Trump’s reaction -- that both sides had been to blame -- was painful, Haley wrote.

“A leader’s words matter in these situations. And the president’s words had been hurtful and dangerous,” Haley wrote. “I picked up the phone and called the president.”

Haley said in a Sunday tweet that the book is about “my experience in life and government.”

To contact the reporter on this story: Steve Geimann in Washington at sgeimann@bloomberg.net

To contact the editors responsible for this story: James Ludden at jludden@bloomberg.net, Tony Czuczka

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