British singer Jamelia has hit out at pop newcomer Leona Lewis - calling her a "poor man's Mariah Carey".
The Dreams hitmaker, 26, also dared to have a dig at Leona's mentor, music mogul and X Factor judge Simon Cowell.
She brands Cowell "disrespectful" and claims Lewis does not deserve the hype surrounding her debut.
Jamelia says, "When Simon stops all this stupid hype about her, that's when we'll see if she can deliver. Like every artist Simon has, she'll fade into obscurity eventually.
"Only Will Young has been successful, and that was because he's talented and cut ties with Simon. Leona is a poor man's Mariah Carey.
"Simon's lost it. He is disrespectful. Leona may be talented, but she's not worked as hard as me or others in the industry - fact!"
Despite Jamelia's rant, Lewis, who won the British TV talent show The X Factor last year (06), has received much acclaim for her debut A Moment Like This, including the Best Selling U.K. Single gong at the prestigious Ivor Novello Awards earlier this year (07).