A reporter asked the president about the theory at a White House briefing Friday after Trump tweeted his congratulations to a QAnon-supporting candidate. Marjorie Taylor Greene, who won her House primary runoff in Georgia this week, has called the theory "something worth listening to and paying attention to" and called its source, known as Q, a "patriot." Trump praised her as a "future Republican Star."

"Well, she did very well in the election. She won by a lot. She was very popular and she comes from a great state and she had a tremendous victory. So absolutely, I did congratulate her," Trump said, sidestepping the question and ignoring a follow-up before moving on to another reporter.

Trump has a long history of advancing false and sometimes racist conspiracies, including on Thursday, when he gave credence to a highly-criticized op-ed that questioned Democrat Kamala Harris' eligibility to serve as vice president even though she was born in Oakland, California.

Asked about the matter, Trump told reporters he had "heard" rumors that Harris, a Black woman and U.S.-born citizen whose parents were immigrants, does not meet the requirement to serve in the White House. The president said he considered the rumors "very serious." Constitutional lawyers have dismissed it as nonsense.