Former President Donald Trump has denounced John Kelly, his ex-chief of staff, for making disparaging remarks about him, including accounts of Trump praising Nazi Germany dictator Adolf Hitler’s generals during his time in the White House.

Kelly, a retired U.S. Marines general, said in remarks published by The Atlantic on Tuesday that he witnessed Trump express an admiration for “Hitler’s generals” while serving as president. The article also reported that Trump said he wanted “the kind of generals that Hitler had” during a White House meeting.

In an interview published by The New York Times on the same day, Kelly said that he believed the former president is a “fascist” and a “dictatorial leader,” claiming that he saw Trump praise “the good things” Hitler did and confirming his past account of Trump calling U.S. soldiers killed or injured in action “losers and suckers.”

Trump weighed in on Kelly’s remarks in a post to Truth Social on Wednesday, claiming that his longest-serving White House chief of staff was a “lowlife” who simply “made up” his recollections while diagnosing him with “Trump Derangement Syndrome.”