WATCH | Gingers unite as Ed Sheeran & Prince Harry star in 'hairlarious' video

“It's like looking in the mirror,” Prince Harry jokes as he opens the door to pop superstar Ed Sheeran in a video shared on the Sussex Royal Instagram account.

The famous pair have collaborated to promote World Mental Health Day in a video that pokes fun at the fact that they're both redheads.

We don't want to spoil the punchline, so watch it below:

Prince Harry and his wife, Meghan, spoke about the importance of talking about mental health during their recent tour of SA. 

While in Cape Town, the Duchess told the media that she felt there was a global “consciousness crisis”.

"No matter where you are in the world, if you're in a township or a big city ... everyone is dealing with a different version of the same thing, she explained.

“We're all trying to power through and find some optimism.”

The royal couple emphasised that people needed to be willing to open up about their mental health issues, and to know that there are people who would be willing to listen to them.

It's a message they reiterated on Instagram on World Mental Health Day, saying, “There’s no need to suffer in silence - share how you’re feeling, ask how someone is doing and listen for the answer. Be willing to ask for help when you need it and know that we are all in this together.”