Instead, Biden said he wanted to devote his time to speaking about addiction and recovery, which he described as a cause capable of bridging America's political divides.

"I believe that addiction and the hope of recovery are something that connect us all," he said.

Asked what made him proudest of his father, Hunter Biden pointed not to his years in public office but to his resilience.

"I'm most proud of his resilience," he said. "He's proven time and time again that when you get knocked down, you can get up.

"He's the toughest man I know."

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