Rex Tillerson reportedly called Trump a 'moron' - and wanted to resign this summer

US Vice President Mike Pence and other top officials intervened to persuade Secretary of State Rex Tillerson not to resign during the summer as tensions rose between President Trump and the nation's top diplomat, NBC News reported on Wednesday.

In July, Pence met with Tillerson in an effort to ease growing discord over policy, NBC reported, citing 12 current and former senior administration officials and other people close to Trump.

Their meeting came days after Tillerson, in a session with Trump's national security team and Cabinet officials at the Pentagon, openly criticized the president and reportedly called him a "moron," NBC said, citing three officials familiar with the incident.

As NBC notes, Tillerson's "moron" comment followed a meeting on Afghanistan where Trump compared "the decision-making process on troop levels to the renovation of a high-end New York restaurant." Also around this time, Trump made a politicized speech to the Boy Scouts of America, which Tillerson once led.

Representatives for the State Department and the White House did not immediately respond to requests for comment on the NBC report by Reuters.

Tillerson, in late July, had weighed whether to return to Washington from a personal trip to Texas but was reassured after discussions with General John Kelly, now Trump's chief of staff, and Defense Secretary James Mattis, the network reported, citing four people with direct knowledge of the exchanges.

Tillerson said publicly in late July that he was "not going anywhere."

The White House declined to comment to NBC, and a State Department spokesman told the network Tillerson did not consider quitting in July and did not call the president a moron.

"Wow, so many Fake News stories today. No matter what I do or say, they will not write or speak truth. The Fake News Media is out of control!" Trump tweeted Wednesday morning shortly after NBC published its report. It was not clear what stories Trump was disputing.

Over the weekend, Tillerson said the United States had direct channels of communication with North Korea to see if it was interested in dialogue in hopes of reducing tensions. The next day on Twitter, Trump said Tillerson was "wasting his time."

After the NBC report on Wednesday morning, foreign policy experts came out to encourage Tillerson to resign.

"Rex Tillerson has been dealt a bad hand by the Potus & has played it badly. For both reasons he cannot be effective Sec State & should resign," Council on Foreign Relations President Richard Haas tweeted.

Haas wrote it would be hard for anyone to be successful as Secretary of State right now, given Trump's policies such as leaving TPP and the Paris climate according, as well as the lack of staff and money given to the State Department, and the role of White House staff. Haas also cited Trump's tweeting habits as an impediment.

Likewise, Eurasia Group President Ian Bremmer tweeted that Tillerson should leave his position.

"I know Rex and he's extremely capable. But he's now in an impossible position & should step down," Bremmer said.

Tillerson is not the only Cabinet official to have publicly diverged from the president on policy issues.

Mattis said on Tuesday the United States should consider staying in the Iran nuclear deal unless it was proven that Tehran was not abiding by the agreement or that it was not in the U.S. national interest to do so.

Trump has called Iran's 2015 deal with six world powers an "embarrassment."

Mattis has played down any tensions between Trump and Tillerson over their apparent split, most recently over North Korea.

Trump's White House and State Department have also taken differing stances on other foreign policy issues.

Earlier this year, Trump backed Gulf Arab leaders in their boycott of Qatar even as Tillerson and the Pentagon cautioned against the military, commercial and humanitarian effects of the dispute.