Charles Ventura

USA TODAY

During a White House meeting with congressional leaders from both parties Monday, President Trump reportedly told lawmakers he would have won the popular vote against Hillary Clinton if it weren't for voter fraud, reviving his unsubstantiated claim about illegal voting.

The Washington Post, who first reported the conversation, claims Trump spent 10 minutes of the meeting "rehashing the campaign," claiming that 3 to 5 million illegal votes on election night cost him the popular vote. The New York businessman won the Electoral College, but his Democratic rival won the popular vote in November by nearly 2.9 million votes.

Trump, who has made the unverified claims about voter fraud before the election, incorrectly commented about his win back in a series of tweets in the weeks following the election. "In addition to winning the Electoral College in a landslide, I won the popular vote if you deduct the millions of people who voted illegally," Trump said on Twitter.

House Majority Leader Kevin McCarthy, R-Calif., said he heard Trump's comments about the popular vote, but he did not elaborate on what was said. "We talked about different electoral college, popular vote going through the different ones," McCarthy said according to The Post. "Well, we talked about going back through past elections. Everyone in there goes through elections and stuff so everybody's giving their different histories of different parts."

House Democratic Leader Nancy Pelosi, D-Calif., who was asked about any surprises during the meeting, said she wouldn't "even go into that.”

After numerous studies conducted before and after the election, researchers found no evidence to support Trump’s unsubstantiated claim.

Back in November, former House speaker Newt Gingrich told USA TODAY that Trump's biggest misstep after his win was to assert claims of widespread voter fraud. "The president of the United States can't randomly tweet without having somebody check it out," Gingrich told USA TODAY. "It makes you wonder about whatever else he's doing. It undermines much more than a single tweet."

Contributing: The Associated Press