David Lee Roth (L) sings with Eddie Van Halen at the Saddledome in downtown Calgary, Alberta on May 9, 2012. (QMI Agency/Stuart Dryden)

Rockers Van Halen have postponed their upcoming tour of Japan after Eddie Van Halen underwent emergency surgery for a digestive disease.

The guitarist was admitted to hospital for the operation to treat a "severe bout" of diverticulitis, a disease of the large intestine, and is expected to make a full recovery within four to six months.

As a result, the band has been forced to cancel its November shows in Japan.

A post on the group's website reads, "Eddie Van Halen underwent an emergency surgery for a severe bout of diverticulitis. No further surgeries are needed and a full recovery is expected within 4-6 months.

"Van Halen's scheduled November 2012 tour of Japan is currently being rescheduled and the band looks forward to seeing and playing for their fans in 2013."