She said: "Will I be singing? Definitely. I'd perform every week if I had my say."
The 'Don't Hold Your Breath' hitmaker also promised to do as much as she can to help the contestants through the competition.
She said: "I plan to be there to encourage and empower and nurture the artists."
Nicole, 32, also insisted she is not worried about out-doing judges Paula Abdul and Cheryl Cole in The Fashion stakes, but promised to "up her game" when the show reaches the live stages of the contest.
She told Britain's Star magazine: "We are three such different women. We are all individuals. There's so much room for us all.
"We're at the beginning of the process, so you want to look and feel your best. The Days are really long so you want to keep it smart-casual. When we get to the live shows, I'll up my game."
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