White House Press Secretary Sean Spicer was grilled this afternoon by multiple reporters on whether President Donald Trump believes that millions of votes were illegally cast in November's election.

Spicer did not back off Trump's claim, which was reportedly made by the president in a meeting Monday with lawmakers. 

Trump first made the claim after the election in a tweet, writing that, "I won the popular vote if you deduct the millions of people who voted illegally."

A reporter asked Spicer today for specific evidence to back up the claim, noting that House Speaker Paul Ryan (R-WI) said there is "no evidence."

"The president has believed that for a while based on studies and information that he has," said Spicer. 

Another reporter followed up a few minutes later, asking whether the White House will ask for a formal investigation of voter fraud or illegal immigrants casting ballots.

"It's a belief that he has maintained for a while, a concern that he has about voter fraud," Spicer answered, adding that Trump is "comfortable" with his victory and made the comment "in passing" to members of Congress. 

"This isn't the first time you've heard this concern of his," said Spicer, citing a 2008 Pew study as one basis for Trump's view on the matter.

Mara Liasson asked Spicer why Trump wouldn't demand an investigation, stating that 3-5 million illegal votes would be the "biggest scandal" in U.S. electoral history. 

"Maybe we will. ... We'll see where we go from here," said Spicer. 

At the conclusion of the briefing, following even more questions, Spicer seemed to dismiss the notion that there would be an investigation. 

Watch the exchange above.

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