U.S. Secretary of State Rex Tillerson dodged questions on Wednesday about whether he once called President Trump a "moron" during a meeting about the administration's Afghanistan strategy.

"I'm not going to deal with petty stuff like that," Tillerson told reporters at an impromptu press conference, after rejecting an NBC News report that described him as frustrated with the president to the point of wanting to resign.

A reporter had asked Tillerson whether he ever explicitly referred to the president as a moron.

"This is what I don't understand about Washington. Again, I'm not from this place. But the places I come from, we don't deal with that kind of petty nonsense," Tillerson responded. "I'm just not going to be part of this effort to divide this administration."

Tillerson said he did not have a chance to speak with Trump, who departed Washington for Las Vegas early Wednesday, before speaking to the media about the report.

The top U.S. diplomat also complimented Trump during his remarks, saying of the president: "He loves this country. He puts Americans and America first. He's smart and he demands results wherever he goes."

"And he holds those around him accountable," Tillerson added. "Accountability is one of the bedrock values the president and I share."