Prom is a night most people never forget.

But Justin Trudeau made the occasion even more memorable for one group of students when he photobombed a picture while out running.

The Canadian prime minister was snapped by his official photographer as he jogged past the well-dressed party-goers on Stanley Park Seawall, in Vancouver, on Friday night.

Spotted! Canadian Prime Minister Justin Trudeau, circled, was snapped as he jogged past a group of teenagers getting ready for prom in Vancouver on Friday night (photo/Mail Online)

While he might have been hoping to slip past without being spotted, one eagle-eyed teenager recognised the prime minister and asked him to pose for a photo.

Living up to his reputation as a laid back leader, Mr Trudeau was happy to oblige and smiled for the camera while still wearing his workout t-shirt and exercise shorts.

Smile! The Canadian leader beamed as he posed for a photo with the excited group (photo/Mail Online)

The photo, taken by photographer Cam Corrado, shows a flushed Mr Trudeau beaming as he poses in the middle of the excited gaggle of teenagers.

The picture, and the original photobomb image, delighted dozens of social media users, with many praising Mr Trudeau for his approachable and laid back nature. 

However others questioned whether original photo, which was shared on Twitter by Mr Trudeau's photographer, Adam Scotti, was in fact a staged publicity stunt.