Drummer Bill Ward has threatened to quit the Black Sabbath reunion over contractual issues.

The original members of the heavy rock supergroup announced plans to record a new album and tour in 2012 at the end of last year - but the get together has been hit by another big problem just a month after guitarist Tony Iommi announced he had been diagnosed with lymphoma.

Drummer Ward insists he is being disrespected by the band's managers and in an open letter to fans, he states he'll walk away from the reunion if he doesn't get a decent contract to sign.

The rocker writes, "At this time, I would love nothing more than to be able to proceed with the Black Sabbath album and tour. However, I am unable to continue unless a 'signable' contract is drawn up; a contract that reflects some dignity and respect toward me as an original member of the band.

"Last year, I worked diligently in good faith with Tony, Ozzy and Geezer. And on 11/11/11, again in good faith, I participated in the L.A. press conference. Several days ago, after nearly a year of trying to negotiate, another 'unsignable' contract was handed to me. Let me say that although this has put me in some kind of holding pattern, I am packed and ready to leave the U.S. for England (where the group is recording). More importantly, I definitely want to play on the album, and I definitely want to tour with Black Sabbath.

"I've realized that I've been getting 'the cold shoulder' (and, I might add, not for the first time). Feeling somewhat ostracized, my guess is as of today, I will know nothing of what's happening unless I sign 'the unsignable contract'."

He continues: "The place I'm in feels lousy and lonely because, as much as I want to play and participate, I also have to stand for something and not sign on. If I sign as-is, I stand to lose my rights, dignity and respectability as a rock musician." (KL/WNWC/MT)