The 25-year-old model and DJ, who is participating in the reality TV series alongside stars such as Kerri-Anne Kennerley and former Neighbours actress Erin McNaught, admitted that she wants to win the show.
When asked if she has been 'trash-talking' her rivals, Williams told National Features: "Not yet, but I'll let you know." McFadden added: "As soon as the live shows start, it'll be on... 'This one's a bitch, that one's a...'"
Williams countered: "Shut up, you're making me sound like a bitch. But seriously, I don't think there's anybody in this who's not trying to win the show. Otherwise, why would you bother?"
When she was asked if she is competitive, Australia's Got Talent judge McFadden said to Williams: "You're the most competitive person I've ever met. She's already been scanning Twitter going, 'Erin is doing five hours [training], Kerri-Anne's doing six'. Then she's ringing her partner screaming, 'We've gotta do more hours'."
He added: "I think it's great, I'm delighted for her. It's a great opportunity for people of Australia to get to know her, instead of just in magazines. She's got a great personality and this is going to be a great challenge."
Williams said: "I'm just going to be myself and hope that people like me. I don't really feel the pressure."
Dancing with the Stars premieres on Sunday, April 15 at 6.30pm on the Seven Network.
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Watch the Dancing with the Stars 2012 promo below: