Ed Sheeran has transformed a packed audience into a "gospel choir" and then walked off stage leaving them singing one of his most famous songs.

The flame-haired hit maker was playing at the iTunes Festival in the Roundhouse in Camden, north London, with a set list that included what he described as a "big climactic orgasm of music".

Sheeran encouraged the crowd to sing along throughout the gig, asking them to be his "gospel choir of Camden".

When the 23-year-old star, wearing his trademark checked shirt, returned to the stage for his encore, fans went wild as he burst into a rendition of his hit Sing.

Sheeran told the crowd to keep singing the song's catchy riff and not to stop, and then he finally ended his set by walking off stage as fans continued to sing.

The singer-songwriter took a photo of his audience during the concert and, due to it being streamed online around the world, he asked them to "say hi to Mongolia".

Sheeran sang songs from his current album X as well as previous hits such as The A Team and You Need Me, I Don't Need You.

He also performed a duet with Foy Vance from Northern Ireland, who was his support act.