LOS ANGELES (Reuters) - Rock singer Ian Astbury has quit the Doors revival band formed by two of the legendary group's members, and will resurrect his old combo the Cult, he said on Thursday.

Astbury convincingly filled the late Jim Morrison's shoes in Riders on the Storm for the past four years, playing alongside original Doors members, keyboardist Ray Manzarek and guitarist Robby Krieger.

The new group was originally called the Doors of the 21st Century, until Manzarek and Krieger lost a lawsuit filed by former Doors drummer John Densmore, who said the Doors name was being cheapened on the oldies tour circuit.

"I have decided to move on and focus on my own music and legacy," Astbury, 44, said in a statement. "I have enjoyed performing and sharing the stage with Ray Manzarek and Robby Krieger immensely. I have learnt a great deal from the both of them, and it certainly has expanded my abilities as a performer. This has been a difficult decision to make but I feel I would be holding them back as well as myself if I did not depart at this time."

Astbury has reconnected with Cult guitarist Billy Duffy to relaunch the hard rock band famed for such late-'80s hits as "She Sells Sanctuary," "Fire Woman" and "Spiritwalker."