Tony Iommi has teased his "really good" upcoming collaboration with Ozzy Osbourne.

The 'Scent of Dark' musician has written a track for his former Black Sabbath bandmate's upcoming solo album, on which he also plays guitar, and he is very impressed with the song, which also featured Red Hot Chili Peppers' Chad Smith.

He said: “I wrote the whole track and played on it and played the solo on it,” he said. “It’s horrible, really….No. I’m joking. No, it’s good. It’s really good. And I like what Ozzy sang on it. I think he did a really good job. And I think they had Chad play drums on it. I’ve left it in their hands now.”

Although Tony and Ozzy are in regular contact, they "don't really speak" directly because the 'Paranoid' singer gets confused by different time zones in the US and UK so they largely communicate by text.

Tony told Rolling Stone magazine: “We’re in touch quite a lot. We don’t really speak because we are useless on the phone, the pair of us. I think we stopped that when he used to phone me at 2 o’clock in the morning and I’d go, ‘Oz, it’s 2 o’clock in the morning.’ ‘Oh, oh, sorry. All right. Bye.’

“He forgets about what time it is in England, and of course when the phone goes at that time of the morning you think, ‘Oh, Christ. What’s that? Somebody’s died or something has happened.’ And of course it’s him going, ‘Oh, oh, oh, oh, sorry. I didn’t know it was that time.’ So we tend to sort of just text now."

Meanwhile, Ozzy recently revealed he is delighted that Metallica bassist Robert Trujillo - who he toured with in the 1990s - will also feature on his upcoming solo album.

He said: "Rob has always been a great friend of mine.

"He's a great bass player and a great guy; he's the only guy who, when it came time to move, did things the right way.

"I always ask that the guys who play with me, if they get another offer and want to move on, that's fine, just don't drop me in the s***, give me time to get a replacement.

"Rob is the only guy that did right by me for that.

"I'm really happy we've got him playing on the new album as well."