"I did not undercut anybody", he also told reporters.
President Donald Trump bragged on Tuesday that he would beat Secretary of State Rex Tillerson in an IQ test and Mensa says it's time to prove it.
Trump issued the challenge in an interview with Forbes magazine, when asked about reports that Tillerson called him a "moron" after a classified briefing this summer. "You should get a sense of humour". "I don't believe in undercutting people", he said.
Reports have swirled of a schism in the Trump administration between the commander-in-chief and his top diplomat, as the United States faces a host of vexatious foreign policy conundrums, from North Korea to Iran.
Mr Trump and Mr Tillerson are scheduled to have lunch later with defence secretary Jim Mattis.
On Wednesday morning, NBC reported that during that now-infamous gathering back in July - in a room full of the country's most important national security advisers - the toddler-in-chief threw a temper tantrum when he was shown a chart that illustrated how our country has steadily reduced its nuclear stockpile over the past 50 years.
"I told Rex Tillerson, our wonderful Secretary of State, that he is wasting his time trying to negotiate with Little Rocket Man [Kim Jong-Un]", he tweeted earlier this month.
North Korean hackers stole US-South Korea war plans, official says
In a pair of tweets sent Saturday afternoon, Trump said past agreements with North Korea have all been violated. The U.S. bombers took off from the Andersen Air Force base in Guam, the U.S.
View the comments below to see whether our readers thought it was appropriate for Mr Trump to challenge his own Secretary of State.
There were reportedly several "tense exchanges" at the July 20 meeting, and it's not clear if the comments on nuclear weapons directly led to TIllerson's Trump criticisms.
Mr Tillerson is said to roll his eyes or slouch when he disagrees with the decisions of his boss. News, which broke the "moron" story last week, moved the ball forward today.
Now, however, he's lobbing one of his trademark counter-punches, just in case. Well, he's smarter than Rex, that's for certain. "I think I'm actually strengthening authority".
Mr Trump said on Sunday there needed to be security enhancements - and the border wall he has demanded - before he would sign on to a bill restoring a programme that shields from deportation young people brought to the USA illegally when they were children. That's probably why the "moron" line has prompted such a furious response from the White House and State Department.
He replied: "We have a very good relationship". While Mr Trump is quite comfortable with insult-trading, there's one topic that's clearly off-limits.