President Trump mocked Rex Tillerson as "ill prepared" and “dumb as a rock” as he disputed his former secretary of state's claim that Russian President Vladimir Putin was more prepared than him during a 2017 summit.

“Rex Tillerson, a man who is 'dumb as a rock' and totally ill prepared and ill equipped to be Secretary of State, made up a story (he got fired) that I was out-prepared by Vladimir Putin at a meeting in Hamburg, Germany. I don’t think Putin would agree. Look how the U.S. is doing!” Trump tweeted Thursday.

The president’s comments come after The Washington Post reported that Tillerson told the House Foreign Affairs Committee that Putin, ahead of a key meeting in Hamburg, Germany in 2017, was more prepared for the talks than Trump. A committee aide told the Post that the “discrepancy” in preparation “created an unequal footing” for the talks.

TRUMP LASHES OUT AT TILLERSON AFTER CRITICISM: 'HE WAS DUMB AS A ROCK'

Trump, though, told the Post that he was “perfectly prepared” for his meetings with Putin, saying: “We did very well at those meetings.”

As indicated by the quotation marks inside his tweet, Trump has leveled these insults at his former top diplomat before.

In December, Trump called the former Exxon Mobil CEO “dumb as a rock” following comments he made in an interview with former CBS News journalist Bob Schieffer.

During the sit-down, Tillerson said he and Trump did not share “a common value system” and were “obviously starkly different” in their “styles.”

“When the president would say, ‘Here's what I want to do, and here's how I want to do it,’ and I'd have to say to him, ‘Well, Mr. President, I understand what you want to do, but you can't do it that way. It violates the law, it violates the treaty, you know. He got really frustrated,” Tillerson said. “I think he grew tired of me being the guy every day who told him he can’t do that and let’s talk about what he can do.”

Trump tweeted in response that he “couldn’t get rid of him fast enough.”

REX TILLERSON'S CAREER AS SECRETARY OF STATE UNDER TRUMP

“He was lazy as hell. Now it is a whole new ballgame, great spirit at State!” Trump tweeted last December.

Tillerson, 66, was fired from the White House in March 2018. In leaving, Tillerson said Washington, D.C., can be a “very mean-spirited town.”