Bolton, a longtime foreign policy hawk who Trump fired in September last year over policy differences, also said that the US president had expressed a willingness to halt criminal investigations to give "personal favours to dictators he liked," according to a book excerpt published in the New York Times.
The White House attacked Bolton but did not comment directly on excerpts from The Room Where It Happened: A White House Memoir published on Wednesday in the Wall Street Journal, the New York Times and the Washington Post.
The accusations are part of a book that the US government on Tuesday sued to block Bolton from publishing, arguing it contained classified information and would compromise national security. The government is seeking a court hearing on Friday.
Together, they portray a US president mocked by his top advisers who exposed himself to far more extensive accusations of impropriety than those that drove the Democratic-led House of Representatives to impeach Trump last year.
The Republican-led Senate acquitted Trump in early February. Trump was accused of withholding US military aid last year to put pressure on newly-elected Ukrainian President Volodymr Zelensky to provide damaging information on Democratic political opponent Joe Biden.
"Had Democratic impeachment advocates not been so obsessed with their Ukraine blitzkrieg in 2019, had they taken the time to inquire more systematically about Trump’s behaviour across his entire foreign policy, the impeachment outcome might well have been different," Bolton wrote, according to excerpts of his book published in the Wall Street Journal.
Critics of Bolton note he declined to testify before the House inquiry when his disclosures could have been critical, adhering instead to White House guidance.
Representative Adam Schiff, the California Democrat who led the prosecution of Republican Trump, slammed Bolton for saying at the time that "he'd sue if subpoenaed."
"Instead, he saved it for a book," Schiff said on Twitter. "Bolton may be an author, but he's no patriot."
Still, Bolton's allegations provide new ammunition to critics ahead of the November 3 presidential election, including his behind-the-scenes accounts of Trump's conversations with China's Xi - which, in one case, broached the topic of the US vote.
"Trump then, stunningly, turned the conversation to the coming US presidential election, alluding to China's economic capability and pleading with Xi to ensure he'd win," Bolton wrote, in the most in-depth, damaging portrayal by a Trump administration insider to date and just days after former defence secretary Jim Mattis accused the president of trying to divide America.
Biden said in a statement: "If these accounts are true, it’s not only morally repugnant, it’s a violation of Donald Trump’s sacred duty to the American people."
US Trade Representative Robert Lighthizer said in Senate testimony that Bolton's account was "absolutely untrue."
"I was at the meeting. Would I recollect something as crazy as that? Of course I would," Lighthizer said. "This never happened in it for sure. Completely crazy."
White House spokeswoman Kayleigh McEnany called Bolton "A misguided hawk on foreign policy, but a weak dove of an author" and, on Twitter, quoted Bolton previously praising Trump.
TRUMP 'ERODED' PRESIDENCY
Although Trump's administration had been strongly critical of China's mass detention of mostly Muslim Uighur minority and other Muslim groups, Trump gave Xi a green light in that same meeting, Bolton said.
"According to our interpreter, Trump said that Xi should go ahead with building the camps, which Trump thought was exactly the right thing to do," Bolton wrote, adding another top White House official said Trump made similar comments during his November 2017 trip to China.
Bolton cited an innumerable number of conversations in which Trump demonstrated "fundamentally unacceptable behaviour that eroded the very legitimacy of the presidency."
A former US ambassador to the United Nations and Fox News television commentator, Bolton's hawkish approach had worn on a president weary of foreign military entanglements, officials say.
Trump would sometimes chide Bolton in meetings, introducing him to visiting foreign leaders by saying, “You all know the great John Bolton. He’ll bomb you. He’ll take out your whole country.”
In excerpts published in the Washington Post, Bolton writes that Trump said invading Venezuela would be "cool" and that it was "really part of the United States."
The US government has publicly said it does not favour using force to topple Venezuela's socialist President Nicolas Maduro.
The book also exposed the sometimes dim view that Trump's advisers have of him. During a 2018 meeting with North Korean leader Kim Jong Un, Bolton says he got a note from Secretary of State Mike Pompeo mocking Trump.
"He is so full of shit," Pompeo's note said, according to a Bolton excerpt in the Washington Post.
Although Trump is publicly critical of journalists, Bolton's book quotes the US president making some of his most alarming remarks to date.
In a 2019 meeting in New Jersey, Trump allegedly said journalists should be jailed so they have to divulge their sources: "These people should be executed. They are scumbags,” according to another excerpt in the Post.
