"We did not have a common value system," Tillerson said during an interview in which he slammed President Trump
Credit: JIM WATSON/AFP/Getty

Rex Tillerson isn’t holding back.

In an interview with CBS News’ Bob Schieffer during a fundraiser in Houston on Thursday, the former Secretary of State slammed President Donald Trump, calling him “undisciplined” and prone to asking for unlawful requests.

“I had never met Donald Trump until the day he asked me to be Secretary of State,” the former head of ExxonMobil remarked during the rare public appearance, adding that while Trump’s decisions can often seem impulsive to an outside eye, he believes that Trump is just “trying to act on his instincts.”

“It was challenging for me,” he said of his former job, “to go to work for a man who is pretty undisciplined, doesn’t like to read, doesn’t read briefing reports, doesn’t like to get into the details of a lot of things, but rather just kind of says, ‘Look, this is what I believe.’ ”

During the interview, Tillerson, 66, also claimed that the president, 72, would frequently ask him to undertake actions that would “violate” a law or treaty.

“We did not have a common value system,” Tillerson added, according to CBS News. “When the president would say, ‘Here’s what I want to do and here’s how I want to do it,’ I’d have to say to him, ‘Mr. President, I understand what you want to do, but you can’t do it that way. It violates the law. It violates a treaty.’ ”

“You know, he got really frustrated,” Tillerson continued, reflecting on what led to his firing. “I think he grew tired of me being the guy every day that told him, ‘You can’t do that, and let’s talk about what we can do.’”

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In March, Trump announced on Twitter that Tillerson was being replaced by Mike Pompeo, who was then director of the CIA.

The State Department went on to confirm to CNN that Tillerson found out he was fired from Trump’s tweet. Two other sources told CBS News’ Margaret Brennan the same thing.

Throughout his time in office, Tillerson had a complicated relationship with the president.

In 2017, Tillerson made headlines after he reportedly called the president a “f—— moron” in a meeting. Afterwards, he hastily arranged a press conference at the State Department to reaffirm his commitment to Trump, and notably declined to address the comments specifically.