The ITV show – which sees disguised celebrities sing to a panel of judges – began at the weekend, prompting viewers to try to guess who is behind each mask.
Pussycat Doll Roberts was asked by Jamie Theakston and Amanda Holden on Heart Breakfast radio about speculation she is appearing as The Masked Singer’s Octopus or Daisy.
Roberts replied: "I mean I've had a crazy-busy schedule lately. I love a costume. I mean, you know I do like to have a little dress-up."
Theakston asked if she was Daisy, to which Roberts responded: "I think you need to watch the show and find out, don't you? Don't you? Don't you?”
She added: "I don't know who it is. I really don't.”
Theakston and Holden told listeners the singer wasn't making eye contact and was looking "very shifty".
Roberts laughed: "I don't know who it is, though. I mean, I'm not sure, so yeah… Anyways, shall I get back to some showbiz stuff.”
Since the show began last weekend, former Labour MP Alan Johnson and EastEnders star Patsy Palmer have been eliminated and unmasked.
Other celebrities believed to be behind the masks include Denise Van Outen, CeeLo and Jodie Marsh.
Model and reality star turned bodybuilder Marsh has denied she is Octopus.
She tweeted: “I promise it’s not me. I don’t even know what the show is?! I just got a load of tweets.”
The Masked Singer – featuring Jonathon Ross, Rita Ora, Ken Jeong and Davina McCall on the judging panel and presented by Joel Dommett – returns to ITV on Saturday 11 January at 7pm.