Katy Perry & Justin Trudeau Seen on Dinner Date in Montreal

Katy Perry is saying "bon appétit" to Justin Trudeau ... as the pair was seen chowing down at a swanky restaurant in Montreal.

In new footage -- obtained by TMZ -- the pop star and former Canadian Prime Minister were seen dining together Monday night at Le Violon.

Katy appears interested in what Trudeau has to say, leaning in across the table during what looks like a thoughtful conversation.

An eyewitness tells us the two sipped cocktails and shared several dishes ... including one with lobster.

Apparently, security guards were keeping tabs on both of them ... sitting at the bar with their backs turned, monitoring the date through the mirrored glass.

At one point, we're told the chef came to greet the duo ... and after their meal, KP and JT made their way to the kitchen to thank the staff personally.

Katy's making her way through Canada while on tour ... performing tonight in Ottawa, with another show tomorrow back in Montreal.

As you know, Katy's been enjoying single life following her split from Orlando Bloom -- the two share a daughter. Meanwhile, Trudeau and his ex-wife Sophie separated in 2023 after an 18-year marriage.