This Queen song which comes from their early 1974 album A Night At The Opera was written by Queen's Brian May.
George performed the song as the opener for his critically highly acclaimed performance at the Freddie Mercury Tribute concert at London's Wembley stadium in 1992.
It was Queen's repertoire amongst others which George "used to busk on the Underground" before fame and he was also a big admirer of Freddie. So George must have felt very honored to be able to play with the remaining band with whom he produced the track.
It appears on the video release "The Freddie Mercury Tribute":