Cheryl and Derek were regularly spotted together throughout 2010 and he even rushed to the Girls Aloud star's bedside when she fell seriously ill with Malaria.
But although they were constantly pictured looking close, neither Cheryl or Derek have ever gone on the record about the depth of their relationship - until now it seems.
Speaking at a BBC Worldwide Dancing With The Stars event in London, Derek reportedly said: "We dated for a while. Absolutely we are still friends, we are very close."
He is also said to have told reporters: "I don't speak about my time with her because I think often in this culture people take advantage of their friendships...
"I've never spoken about her because her friendship is important to me."
Derek was asked about Cheryl's new man, dancer Trey Holloway, and admitted that he had not yet been introduced to him.
"I have heard he's a great guy. I'm not sure she has a thing for dancers but let's say she definitely goes for creative types," he is quoted as saying.
Cheryl was an unknown in the US when she was first introduced to Derek. They grew close following her split from her ex-husband Ashley Cole but have not been pictured together for years.
In her book, Cheryl: My Story, she talks a lot about the professional dancer. But she never confirms whether they dated or not.
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