JUDAS PRIEST bassist Ian Hill hasn't ruled out the return of fellow PRIEST co-founder Kenneth "K.K." Downing.

The guitarist, who left the group in 2011 amid claims of band conflict, shoddy management and declining quality of performance, has made it clear that he is willing to come back to the band following Glenn Tipton's decision to retire from the road due to his battle with Parkinson's disease.

Asked in a new interview with Riff Magazine what his thoughts are on the possibility of Downing rejoining PRIEST, Hill said: "It's a difficult call. I mean, Richie [Faulkner] took over from Ken. He's done an absolutely tremendous job, he really has. And he's made Ken's parts his own now. He's got his own angle on the lead breaks. Ken's part's been taken, and there's no plans to have Ken back, really. Hey, listen, never say never. But at the moment, we're going along quite well without Ken, so it could stay like that, I think, at least for the foreseeable future."

During the same chat, Hill confirmed that PRIEST is planning to celebrate its 50th anniversary in 2020. "That'll come next year; we're planning on a celebratory tour next year," he said. "We weren't actually known as JUDAS PRIEST in 1969. Ken Downing, myself and a guy called John Ellis formed in '69, but we weren't called JUDAS PRIEST, actually, until 1970, so we'll start celebrating next year."

Last fall, Downing dismissed as a "load of bollocks" Hill's explanation for why K.K. wasn't invited to rejoin the band after Tipton's Parkinson's diagnosis was made public.

"We were like brothers; we went to infant school together and secondary school together, and we lived our career together," Downing said. "But I'm not totally happy about what's being said. Ian seems to be [saying] things like, 'None of the fans are missing K.K.,' and, 'Richie has brought a new energy to the band.' And I'm going, 'Ian, dude, on that last tour, I was the energy. I slowed down because people weren't keeping up with me.'… So I'm thinking, Ian, get a grip with yourself, mate. You've just replaced the energy with some energy. Fine — well, great. But that's not moving forward, Ian."

Tipton was diagnosed with Parkinson's disease five years ago — after being stricken by the condition at least half a decade earlier — but announced in February 2018 he was going to sit out touring activities in support of PRIEST's latest album, "Firepower".

Last summer, Downing revealed that he sent two resignation letters to his bandmates when he decided to quit JUDAS PRIEST. The first was described as "a graceful exit note, implying a smooth retirement from music," while the second was "angrier, laying out all of his frustrations with specific parties."

Downing later said that he believed the second letter was "a key reason" he wasn't invited to rejoin PRIEST after Tipton's decision to retire from touring.