United Kingdom, Oct. 29 -- Katy Perry and Justin Trudeau "have fun together".

The 41-year-old pop star and the former Canadian Prime Minister began dating earlier this year, and Justin is said to be having a lot of fun with Katy, following a difficult split from his wife, Sophie Gregoire.

A source told People: "Justin has had a lot of upheavals in the past couple of years, both in his professional-political status and at home with the split from Sophie."

Justin, 53, is "much happier" and he's now loving life with the chart-topping pop star.

The insider shared: "He is a much happier person now. Stresses are greatly diminished. And he is intrigued with Katy. They have fun together, laugh a lot, talk about everything.

"His life is much ...