WATCH: Rubio said he's never seen Trump fall asleep in a meeting. Rep. Lieu showed him the videos

Rep. Ted Lieu, D-California, and Secretary of State Marco Rubio had a tense exchange in a congressional hearing Wednesday over President Donald Trump dozing off in public appearances, like Cabinet meetings.

Watch the exchange in our video player above.

Lieu asked Rubio to focus on the president, whose eyes are closed, in a video of a Cabinet meeting in December.

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"Secretary Rubio, have you been at more than one meeting where President Trump has fallen asleep?" the Democratic lawmaker asked during Wednesday's House Foreign Affairs Committee hearing.

Rubio said that was false.

"I've never seen him fall asleep," he said. "On the contrary, the guy doesn't sleep, which is a big problem," adding that Trump has called him in the early morning hours.

"Secretary Rubio, I'm going to show you in a moment a video that shows you just lied to Congress."

A video of last month's Cabinet meeting then plays. Trump is again shown sleeping, while Rubio is speaking about wartime matters.

"You are literally talking about issues of war and peace and Donald Trump is sleeping right next to you," Lieu said, repeating that Rubio was lying to Congress.

Rubio again said Trump wasn't asleep, saying that the videos being shown in the hearing aren't showing the president is dozing off.

"The president's inability to stay awake on the job has caused other countries to perceive him differently," Lieu said. "They mock him."

A third video was then shown of a foreign news segment about Trump "fighting sleep" at a Memorial Day ceremony. Lieu said the video stresses how Trump's public sleeping shows there's "something very wrong" with his health and cognitive abilities and has contradicted himself in the same meeting or interview.

Rubio called Lieu's questioning "absurd," saying there was a "cognitively impaired president" in the White House, alluding to former President Joe Biden without saying his name, while he continued to defend Trump's mental fitness.

"Just keep lying, Secretary Rubio, just keep lying," Lieu said.

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