The current X Factor co-host told The Mirror that rumours of a romance were a "load of rubbish" and the two singers are nothing more than friends.
"We've known each other a long time," he added.
"We laughed about it. What? We're casually dating? No, we're not. We find it funny."
Olly split from long-time girlfriend Francesca Thomas in September, after three years together. She'd always remained out of the limelight and very little was known about her.
In an interview with ITV's Loose Women in October, Olly said: "I've just gone through a break up with my girlfriend, which has been quite sad, quite a difficult couple of weeks."
He also denied (yet again) the endless speculation he has or could hook up with X Factor co-host Caroline Flack, who is also single. "Me and Caroline have always said hundreds of times (in interviews) that we're never going to get together, we're just really good mates."
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