CNN  — 

Former White House chief of staff, retired Marine Gen. John Kelly, has told friends that President Donald Trump “is the most flawed person” he’s ever known.

“The depths of his dishonesty is just astounding to me. The dishonesty, the transactional nature of every relationship, though it’s more pathetic than anything else. He is the most flawed person I have ever met in my life,” the retired Marine general has told friends, CNN has learned.

The reporting comes from a new CNN special scheduled to air Sunday night, “The Insiders: A Warning from Former Trump Officials,” in which former senior administration officials – including former national security adviser John Bolton, former Health and Human Services scientist Rick Bright and former Department of Homeland Security general counsel John Mitnick – explain why they think the President is unfit for office.

Kelly’s sentiments about the President’s transactional nature and dishonesty have been shared by other former members of the Trump administration who also appear in the special.

Olivia Troye, a former top adviser to Vice President Mike Pence, has said the President knew about the impact the coronavirus pandemic would have on the US by mid-February, but that “he didn’t want to hear it, because his biggest concern was that we were in an election year.” Miles Taylor, a former DHS chief of staff who now serves as a CNN contributor, has asserted Trump essentially calls individuals within the federal government who disagree with him “deep state.”

Elizabeth Neumann, another former DHS official, had criticized Trump for not condemning White supremacy after the first presidential debate in September.

“The fact that he continues to not be able to just point-blank say, ‘I condemn White supremacy.’ It boggles the mind,” she told CNN at the time.

Trump did say on Thursday during a town hall on NBC that he condemned White supremacy. “I denounce White supremacy, OK?,” Trump told NBC’s Savannah Guthrie. “I’ve denounced White supremacy for years.”

The President sometimes is successfully cajoled to condemn White supremacists, but often – such as in the first presidential debate – seems reluctant do so, perhaps so as to not alienate any potential votes.

Kelly, who left the White House under contentious circumstances in January 2019, has occasionally voiced criticisms of the Trump administration since leaving his post.

In June, in the wake of George Floyd’s killing at the hands of Minneapolis police and Trump’s response to the subsequent protests and calls for racial justice, Kelly said he agreed with former Secretary of Defense Gen. Jim Mattis’ stark warning that Trump is “the first president in my lifetime who does not try to unite the American people.” Kelly said he would have cautioned Trump against the idea of using law enforcement to clear Lafayette Square of protesters ahead of the President’s now infamous photo op in front of a nearby church.

Kelly also defended retired Army Lt. Col. Alexander Vindman for raising concerns about the President’s call with Ukrainian President Volodymyr Zelensky – the call at the heart of the President’s impeachment. And Kelly has said he believes Bolton’s allegation that Trump conditioned US security aid to Ukraine on an investigation into political rivals.

Kelly has said that before he left the White House, he cautioned Trump: “Don’t hire a ‘yes man,’ someone who won’t tell you the truth. … Because if you do, I believe you will be impeached.”

Since Kelly’s departure, the White House and the President have maintained that the former general wasn’t cut out for his job in the West Wing.

“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.”

This story has been updated with additional background.

CNN’s Maegan Vazquez contributed to this report.