"Jimmy Kimmel Live"/ABC; YouTube, Getty Images
The incident occurred when Perry was in 5th grade and Trudeau was a few years younger than him.
"I have a story about him that I'm not proud of," said Perry, who is half Canadian, on Wednesday's episode of ABC's "Jimmy Kimmel Live."
"My friend Chris Murray, who was also in the fifth grade, reminded me that we actually beat up Justin Trudeau. We both beat him up."
Perry said that he and Murray did it out of "pure jealousy," because Trudeau "was excelling in a sport" that neither of the older boys did.
"His dad was the prime minister," Perry said before pointing out that Trudeau had no security at the time and agreeing with the host that no one would get away with bullying President Donald Trump's youngest son, Barron Trump.
"I don't think that's the reason we beat him up," Perry continued. "I think he was the only kid in school we could beat up. I'm not bragging about it. It was terrible. I was a stupid kid. I didn't want to beat him up. In fact, I think at one point I tried to turn it into love play."
After Perry and Kimmel agreed on Trudeau's good looks, the actor explained why he believes the fight could have propelled Trudeau to his current position.
"I think it was instrumental in him going to such great heights and becoming the prime minister," Perry said. "I think he said, 'I'm going to rise above this, and I'm going to become prime minister.'"
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