Trump shared one heavily edited video on Twitter, which was first featured on Fox News, accusing the speaker of "stammering" through a news conference. Pelosi said Facebook knows the videos are false and should take them down.

"We have said all along, poor Facebook, they were unwittingly exploited by the Russians. I think wittingly, because right now they are putting up something that they know is false. I think it's wrong," she said. "I can take it ... But [Facebook is] lying to the public."

Pelosi added, "I think they have proven — by not taking down something they know is false — that they were willing enablers of the Russian interference in our election."

Facebook did not immediately respond to a request for comment.

On Impeachment, 'We'll Go Where the Facts Take Us'

Pelosi was speaking to KQED News less than two hours after special counsel Robert Mueller made his first public comments on his two-year investigation into Russian interference in the 2016 presidential election. She didn't give much ground on impeachment, but pledged that Democrats will continue to probe President Trump.

"We'll go where the facts take us," Pelosi told KQED's Scott Shafer.