Reznor, who worked with Manson in the early-90s, described the singer as a “malicious guy” who will “step on anybody's face to succeed and cross and line of decency”.

"Seeing him now, drugs and alcohol now rule his life and he's become a dopey clown,” Reznor added, according to Spinner.

The Nine Inch Nails star had an influential impact on Manson's early career, producing the singer's former band Mrs Scabtree's debut album in 1994.

But in an interview with Mojo, Reznor expressed his concern for Manson - and said his frustration with the singer dated back to Nine Inch Nails Download Spiral tour in 1994/5.

"He used to be the smartest guy in the room. And as a fan of his talents, I hope he gets his shit together," Reznor is quoted as saying.

“During the Spiral tour we propped them up to get our audience turned on to them and at that time a lot of the people in my circle were pretty far down the road as alcoholics. Not Manson.

“His drive for success and self-preservation was so high, he pretended to be fucked up a lot when he wasn't."

Reznor's comments follow his recent feud with Chris Cornell, which started on the micro-blogging website Twitter.

(by Jason Gregory)