House Speaker Paul Ryan reacted to the release of leaked audio of him criticizing then-Republican presidential nominee Donald Trump.

The audio, from an October 10, 2016 conference call with his Republican caucus members, was recorded a few days after a leaked Access Hollywood tape of Trump saying he could fondle women made the rounds.

"I am not going to defend Donald Trump. Not now, not in the future... I have real concerns with our nominee... I am doing what I think is best for you, the members," Ryan said on the tape.

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LEAKED AUDIO: Paul Ryan Says He's 'Not Going to Defend Donald Trump'

On "The First 100 Days," Ryan dismissed the recording as "ancient history."

"It's no secret Donald and I had our ups and downs during the campaign," Ryan said. "We merged forces at the end of the campaign."

Ryan said the release, which Martha MacCallum reported may have occurred to coincide with ObamaCare replacement negotiations, doesn't bother him.

"I've got a really thick skin," he said. "I don't really give [the remarks] much thought."

Listen to the leaked audio HERE.

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