President Donald Trump challenged Secretary of State Rex Tillerson to compare IQ tests after Tillerson reportedly called the president a "moron".
"I think it's fake news, but if he did that, I guess we'll have to compare IQ tests. And I can tell you who is going to win," Trump said in an interview with Forbes magazine published Tuesday.
Trump's tense relationship with Tillerson went public following a recent report by NBC News saying Tillerson was on the verge of resigning over the summer amid mounting policy disputes with Trump and that Vice President Mike Pence urged him to remain secretary of state at least until the end of the year.
Citing three anonymous officials, the report also claimed that Tillerson called Trump a "moron" after a July 20 meeting at the Pentagon with members of Trump's national security team and Cabinet officials.
His spokeswoman denied the allegation, however, saying he never used such language.
In the Forbes interview, Trump also reacted to criticism that he has undermined Tillerson through his provocative posts on Twitter that have interfered directly with ongoing diplomatic efforts.
"I'm not undermining. I think I'm actually strengthening authority," he said.
Speaking at a daily press conference, White House press secretary Sarah Sanders later said Trump's "IQ tests" comment was "a joke and nothing more than that".
"The president never implied the secretary of state was not incredibly intelligent," she said, adding that Trump made a joke and he has full confidence in Tillerson.
"They're working hand in hand to move the president's agenda forward."
