US rapper Eminem has said he was left “really heated” after a song from his forthcoming album, 'Relapse', leaked online.

'Crack A Bottle', a collaboration with Dr Dre, appeared on various file-sharing websites last week in an incomplete form.

'Relapse', Eminem's follow-up to 2004's 'Encore', isn't due to be released in the New Year.

Speaking to Billboard, the rapper said: “It wasn't close to finished, and it even has me doing guide vocals for Dre as a suggestion of how he could lay his verses down.

“It's like someone catches you peeping in your window before you got the Spider Man costume all zipped up! Nobody is supposed to see that.

“We are gonna finish it up though and get it out there how it's supposed to be."

In what was a wide ranging interview with the magazine, Eminem also spoke about claims by producer Swizz Beatz that 'Relapse' features a sequel to the rapper's hit single 'Stan'.

The producer, who called the song 'Stan Part 2', said last month it was “totally genius”.

But Eminem said he hadn't worked with the producer on his new album.

"There isn't a 'Stan 2,' and there won't be. Stan drove his car off a bridge and I'm not writing a song as Stan's ghost. That would just be really corny,” he added.

(by Jason Gregory)