NEW YORK -- Malcolm Young has left AC/DC.

A statement Wednesday from the band's label said: "Unfortunately, due to the nature of Malcolm's condition, he will not be returning to the band."

No details were provided.

The band announced in April that the 61-year-old guitarist was taking a break to focus on his health.

AC/DC will release the album "Rock or Bust" on Dec. 2. They will launch a world tour next year.

Stevie Young, nephew of founding members Malcolm and Angus Young, played guitar on the band's new album and will join them on the tour.

AC/DC includes vocalist Brian Johnson, drummer Phil Rudd and bassist Cliff Williams. Young has performed with AC/DC for 40 years.