Last week, speculation was rife online after the We Found Love singer was spotted leaving Kutcher's bachelor pad in Los Angeles at 4am.
However, when asked about her supposed romance with Ashton at a London press conference for her new movie Battleship yesterday (28th March), Rihanna's face dropped as a journalist questioned her private life.
She then went on to deny the allegations, stating: "Wow, how disappointing was that question. I'm happy and I'm single, if that's what you're really asking."
You can catch RiRi in Battleship when it hits UK cinemas on 11th April.
Watch MTV News on the hour every hour on MTV - Sky Channel 126 and Virgin Channel 134