Washington (CNN) Former Vice President Joe Biden joked in an interview that aired Tuesday that he would challenge President Donald Trump to a push-up contest if the President attacked his age or mental health.

"I would say, 'Come on Donald, come on man. How many push-ups do you want to do here, pal?' Jokingly," Biden said in an interview with MSNBC. "You know, come on, run with me man."

The lighthearted remark -- another example of Biden's determination to focus on Trump rather than the crowded field of Democrats vying for the party's 2020 nomination -- is not the first time the Democratic front-runner has suggested he would take on the President in a show of physical force. He previously made a similar suggestion and rejected the notion that he would be intimidated in a CNN exclusive interview with Chris Cuomo

"The idea that I'd be intimidated by Donald Trump," Biden said with a look that suggested that notion would be foolish. "He's the bully that I knew my whole life. He's the bully that I've always stood up to. He's the bully that used to make fun when I was a kid that I stutter, and I'd smack him in the mouth."

While campaigning for congressional candidates at the University of Miami last year, Biden said he would take on the President after his lewd comments about women in the past.

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