A US appeals court has ordered a new trial in a lawsuit accusing Led Zeppelin of copying an obscure 1960s instrumental for the introduction to the band's iconic track, Stairway to Heaven, which was first released on the band's untitled fourth album in 1971.

Two years ago a federal court jury in Los Angeles found Led Zeppelin did not steal the signature guitar part - or 'riff' in the parlance - from the song Taurus, a song recorded by the US band Spirit.

However, a three-judge panel of the 9th US circuit court of appeals in San Francisco ruled that the lower court judge provided erroneous jury instructions which misled jurors about copyright law relevant to the suit. The case has been returned to the court for another trial.

According to The Guardian, a phone message left with an attorney for Led Zeppelin, Peter Anderson, was not immediately returned.

Michael Skidmore, a trustee for the estate of the deceased Spirit guitarist Randy Wolfe, filed the lawsuit against Led Zeppelin in 2015.

Jurors returned their verdict for Led Zeppelin after a five-day trial at which Led Zeppelin musicians Jimmy Page and Robert Plant testified. Page declares that he composed the music and Plant has claimed he wrote the lyrics. 

50 years have passed since Led Zeppelin recorded their first album. On September 27, 1968, Bonham, Jones, Page and Plant met up at in Olympic Studios in London to begin recording that landmark release. 

36 hours in the studio saw it down and the eponymous first album was complete. Produced by Jimmy Page, the album was released in January 1969 on Atlantic Records.

Led Zeppelin in their 1970s heyday: John Paul Jones, John Bonham, Robert Plant, Jimmy Page