Justin Trudeau was filmed dancing at Katy Perry's Lifetimes Tour show in Montreal on Wednesday, 30 July.
Video shows the former Canadian prime minister, 53, watching along as the "Roar" singer, 40, flew over the crowd on a giant butterfly at the Bell Centre.
It came after Perry and Trudeau had dinner together in the city.
A communications consultant for the restaurant Le Violon confirmed that the former prime minister and the singer spent about two hours at the fine-dining spot, the Associated Press reported.
Perry is due to perform further shows in Quebec City and Toronto on the Canadian leg of her tour.
