01/10/2013 at 05:15 PM EST
Wilko Johnson, the former guitarist for '70s band Dr. Feelgood and current actor on Game of Thrones
, has terminal cancer, his manager has revealed.
"I am very sad to announce that Wilko has recently been diagnosed with terminal cancer of the pancreas. He has chosen not to receive any chemotherapy," his manager Robert Hoy wrote in a post on Johnson's Facebook page
"He is currently in good spirits, is not yet suffering any physical effects and can expect to enjoy at least another few months of reasonable health and activity."
Johnson – who plays the mute executioner Ser Ilyn Payne on the hit HBO show, but is best known to his fans as musician – doesn't plan to slow down much in the next couple of months.
"He has just set off on a trip to Japan; on his return we plan to complete a new CD, make a short tour of France, then give a series of farewell gigs in the U.K.," his manager writes.
In the message, Hoy says Wilko thanks his fans who have "generally made his life such an extraordinarily full and eventful experience."
was first to report on Wilko's diagnosis.