President Trump, after seemingly patching things up with Secretary of State Rex Tillerson following a report that he once called the president a “moron” and considered quitting, has challenged the top diplomat to “compare IQ tests” if he indeed said that.

The president made the comments in an interview with Forbes, for a story published Tuesday.

"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.

Tillerson scrambled last week to counter an NBC News report claiming that Vice President Pence had to intervene over the summer to help convince him not to resign – and that Tillerson called the commander-in-chief a “moron.”

Tillerson adamantly denied he considered resigning, while a spokeswoman later pushed back on the “moron” anecdote, though reporters stood by the account.

Trump has at times appeared to undercut Tillerson's message on some of America's most sensitive national security challenges, including Iran and North Korea. Tillerson also has publicly complained about the White House blocking him from making key appointments.

Still, last week Trump told reporters he has "total confidence" in his secretary of state.

In the Forbes interview, done Friday, Trump responded to criticism that he's undermined his secretary of state through his often provocative tweets that have challenged ongoing diplomatic efforts.

"I'm not undermining," Trump told Forbes. "I think I'm actually strengthening authority."

Tillerson’s public pushback last week also seemed to calm the waters.

Trump on Saturday denied a frayed relationship with Tillerson but said he sometimes wishes Tillerson would be “tougher.”

Tillerson and Defense Secretary Jim Mattis are scheduled to have lunch with Trump Tuesday.

The Associated Press contributed to this report.