Jason Derulo gets ''tired of playing nice'' about his split from Jordin Sparks, but says he has put her firmly behind him.

The 'Talk Dirty' hitmaker, who ended his relationship with the 25-year-old singer last September after three years of dating, believes he was ''gentlemanly'' about their breakup, even though she later accused him of leasing a BMW he gave her instead of buying it. But he said: ''I do get tired of playing nice.

Especially when people think I did something wrong, or that she broke up with me. But it's so behind me.'' The 25-year-old star isn't looking for a new girlfriend because he is ''married'' to his career, but claims his love life is like a ''a deck of cards'' at the moment.

He told Billboard magazine: ''You can't pull me out of the studio. Songwriting is a muscle. The more you do it, the better you get at it.'' While Jason is still happily single, Jordin recently confirmed she is dating 22-year-old rapper Sage the Gemini.

Asked about photographs of them on her Instagram feed, she said: ''I think they're pretty obvious. We're having fun. He's a really good guy, and the pictures speak for themselves ... I don't just kiss people!''