Hollywood actor Ashton Kutcher rubbished reports that he is cheating on his wife Demi Moore.

Star magazine had reported that the actor's five-year marriage was 'in danger of falling apart' after he was 'caught cheating with a sexy, young 20-something'.

A source told the magazine that Kutcher was seen 'kissing and groping a hot young blonde' at an Italian restaurant Madeo in Los Angeles.

However, 'The Butterfly Effect' star is now making use of his Twitter account to hit back at the allegations, reports imdb.com.

He wrote: 'Star magazine - you don't get to stand behind 'freedom of the press' when you are writing fiction.'