Former U.S. Ambassador to the United Nations Nikki Haley wrote in her new memoir, “With All Due Respect," that former Secretary of State Rex Tillerson and former Chief of Staff John Kelly tried and failed to recruit her to subvert President Trump in order to "save the country," according to the Washington Post.

Why it matters: Haley's allegations add to an already long list of accounts of aides seeking to undermine Trump in the early stages of the administration, including reports that advisers took documents from the president's desk to prevent him from signing them.

Details: In the book, Haley "describes Tillerson as 'exhausting' and imperious and Kelly as suspicious of her access to Trump," per the Post.

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

Haley also writes that Tillerson told her that people would die if Trump went unchecked. She recalls an argument with Kelly and Tillerson over the administration's decision to cut aid to the UN agency that supports Palestinian refugees.

What they're saying: Kelly did not discuss specifics when asked for comment, but he told the Post 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.”

Tillerson did not respond to a request for comment.

The big picture: Haley is popular within the Republican Party and is seen by many as a potential successor to Trump. She has expressed some disagreements with the president — writing in the book that his comments about the white supremacist rally in Charlottesville were "hurtful and dangerous" — but has overall been a defender of Trump since offering her resignation last October.

Haley told the Post that she opposes Trump's efforts to push Ukraine to investigate his political rivals, but said that the conduct is not impeachable: "[D]o I think it’s not good practice to talk to foreign governments about investigating Americans? Yes. Do I think the president did something that warrants impeachment? No, because the aid flowed."

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