Joe Biden laughed off President Donald Trump's suggestion Friday that the former vice president is too old to run for the Oval Office.
"If he looks young and vibrant compared to me, I should probably go home," Biden, 76, quipped in an appearance on ABC's "The View."
"The best way to judge me is to watch, see if I have the energy and capacity. It's a show-me business."
Earlier, Trump, 72, said that Biden and other 2020 candidates are "making me look very young, both in terms of age and I think in terms of energy."
"Well, I think that — I just feel like a young man. I'm so young. I can't believe it. I'm the youngest person. I am a young, vibrant man," the president said. "I look at Joe — I don't know about him. I don't know."
Trump added, "I would never say anyone is too old, but I know they're all making me look very young, both in terms of age and I think in terms of energy. I think you people know that better than anybody."
Trump also had dubbed the former vice president "Sleepy Joe"within hours of his announcement Thursday that he was joining the 2020 race,and called him someone whose "intelligence" had been "long in doubt."
Biden on Friday said, "That's the first time I've ever been referenced that way, it's usually the other end: hyper Joe."
The two septuagenarians have sparred before. At a Florida rally in March 2018, Biden hit out against sexual assault and blasted Trump for his controversial "Access Hollywood" comments about grabbing women's genitals without their consent.
"A guy who ended up becoming our national leader said, 'I can grab a woman anywhere and she likes it,'" Biden said. "If we were in high school, I'd take him behind the gym and beat the hell out of him."
Trump shot back in a tweet: "Crazy Joe Biden is trying to act like a tough guy...He doesn't know me, but he would go down fast and hard, crying all the way. Don't threaten people Joe!"
"I see that you are on the job and presidential, as always," Biden tweeted.