The rumored new couple stepped out together in Montréal recently, and a source tells PEOPLE they're "interested in each other"

The chef who served Katy Perry and Justin Trudeau detailed how they were as guests—and whether they showed any PDA amid dating rumors.

Pop superstar Katy Perry and former Canadian Prime Minister Justin Trudeau were spotted having dinner together at a Montreal fine-dining restaurant Monday night, prompting speculation about a potential connection between the politically engaged public figures.