The two old rockers have been at loggerheads ever since drummer Ward pulled out of a Black Sabbath reunion in 2012 over contractual issues. Ozzy subsequently insisted his old pal wasn't fit enough for a planned tour, which has prompted Ward to demand an apology.
And now it seems the feud may date back to 1979, when Ozzy was dismissed from Black Sabbath.
Ward tells the Quietus, "I'm like the f**king janitor in that band. Most of the time I always got the s**t jobs that nobody wanted to do, but at the time, I thought maybe I was the best guy to do it. I kind of volunteered to do it. Up went my hand.
"It was one of the worst things I've ever done in my life, to be honest with you.
"I didn't want him to leave the band, but I could understand the reasons why. That was a tragic day. That was the day the band imploded."