London (CNN) Prince Harry and Ed Sheeran have teamed up in a video to raise awareness for World Mental Health Day -- with a light-hearted jibe at their own plight as Britain's most famous redheads.

In the video, shared on the official Sussex Royal Instagram account, the famous duo discuss the issue of mental health , and urge everyone to "look out for anybody that might be suffering in silence".

Yet despite the serious message, the video starts on a humorous note. When the pair sit down to discuss their collaboration, Prince Harry explains that Sheeran has the right "skill set" to create a song to help fight the problem.

"This for me is a subject and conversation which is just not talked about enough, I think people all over the world are really suffering," Harry says in a serious tone.

It soon becomes clear that wires have been crossed, when Sheeran begins describing a song he has started writing to challenge the stigma faced by redheads.

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