Black Sabbath icon Tony Iommi has said he hopes to collaborate with Judas Priest’s Rob Halford when “the time’s right.” He added that the project could include writing songs together, but also suggested there could be more to it. The British icons have known each other from years and come from the same part of England, but have never managed to work in partnership to date.

“We’ve talked about it for ages,” Iommi told Metal Hammer. When the time’s right it would be nice to write a track or two, or whatever. I’d like to do that. It’s nice to work with people that you respect and like.” He reported that he hadn’t done much work since Black Sabbath retired last year, explaining: ”I’m not writing at the moment, but I will be. I moved house, and I’ve only just got set up again. It’s great to have a break – you come back fresh.”

Halford fronted Black Sabbath for two shows in 1992 when the band's then-singer Ronnie James Dio refused to open for Ozzy Osbourne, and again for one night in 2004 when a then-returned Osbourne fell ill.

Along with recalling their U.S. debuts, the veteran artists revealed in their first-ever interview together that they couldn’t recall how long they’d known each other. “Blimey, it’s been years,” said Iommi. “Must have been the late ‘60s or early ‘70s.” Halford added: “Yeah, it was around the time I joined Priest, which was in 1971. Or maybe just after. I dunno. I’m trying to forget just how long ago.”

He went on to praise his friend's achievements, saying: “Sabbath’s most important contribution to music is the invention of heavy metal, plain and simple. Tony was the guy that played the first heavy metal riff. And it all started from there.” Iommi responded: “And Priest have made a tremendous contribution. To start from where they did and they’ve gone on and gone on and gone on. And they’ve flown the flag.”

Halford described their home city of Birmingham as “bleak” during their early years. “Escapism, trying to see what’s over the wall, is part of what drives you,” he said. “You’d see other successful bands going to play in London, and it was such a big deal. It was only two hours away, but it was like another planet.”

Iommi agreed: “Coming from Birmingham, trying to break into London was like pulling teeth. They absolutely hated us. We had a gig at this famous club, The Speakeasy, and we died a death… They didn’t ask us back.”