“It’s hard for me, because all my friends and family vote Labour,” she told the Telegraph's Stella magazine, the full version of which will be published this Sunday.
Fernandez-Versini emphasised that she already pays a "f**king lot of tax" and this meant she felt an obligation to pay more attention politically.
The singer - who is worth an estimated £20 million - was reported to say she felt the extra £250 a month tax levied on homes worth £2-3million would "f**k her over" by the Telegraph.
However a representative for Fernandez-Versini has since denied that she said this in relation to the mansion tax.
Fernandez-Versini herself added that references to mansion tax were taken "out of context".
Asked by the Telegraph whether she was going to vote for David Cameron - who she once termed "slimy" - Fernandez-Versini said she hadn't yet made up her mind.
"Not really. I want to hear what everyone’s got to say," she said.
"I’ve always been Labour all my life but I want to hear what they’ve got to say for myself. Now that I’m a mature woman.
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"I feel like a greater responsibility now to vote for who runs our country. And I pay a f**ing lot of tax. So I think that I need to have a really well-informed, well-educated opinion."
Myleene Klass has been a loud opponent of the mansion tax, and claimed that the amount of money used to buy a "mansion" under Labour's guidelines could in fact only pay for "like a garage" in London.
As part of a debate with Labour leader Ed Miliband, Klass ridiculed his taxation policy, saying "you can't just point at things and tax them".
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