NEW YORK (AFP) - Judas Priest's Glenn Tipton, whose aggressive but classically influenced guitar helped shape the direction of heavy metal, announced Monday (Feb 12) that he was retiring from touring due to Parkinson's disease.

The veteran British band said that Andy Sneap, a longtime metal producer, would replace Tipton on a tour that opens on March 13 in Pennsylvania after the release of Judas Priest's 18th studio album, Firepower. The 70-year-old Tipton, a key songwriter for Judas Priest, said that he remained a non-traveling member of the group and did not rule out occasional returns to the stage.

"I want everyone to know that it's vital that the Judas Priest tour go ahead and that I am not leaving the band - it's simply that my role has changed," he wrote in a statement.

The band said that Tipton had been diagnosed 10 years ago with Parkinson's, a degenerative neurological disorder that affects the body's motor system, often causing shaking.

Tipton is still able to play some of the "less challenging" Judas Priest songs but decided to bow out of touring as the disease is progressing, the band said.

Judas Priest's sound was defined by the intense twin-guitar solos by Tipton and K.K. Downing.

While Downing, who has left Judas Priest, played raw, blues-influenced guitar, Tipton, who learned on acoustic guitar, brought a classical flourish that complemented the voice of frontman Rob Halford.

Judas Priest was perhaps most influential in setting the stage for the more mainstream subgenre of "hair metal" with the band's 1980 album British Steel, which featured comparatively accessible songs Breaking The Law and Living After Midnight. Tipton, who on the side travels the world as an avid fisherman, has also released two solo albums.

Judas Priest was nominated for the latest class of the Rock and Roll Hall of Fame but did not make the final cut.