Natalie Portman did '85 per cent' of Black Swan routines

Natalie Portman did "85 per cent" of the dancing on 'Black Swan'.

Natalie's fiance Benjamin Millepied - with who she is expecting her first child later this year - revealed he was impressed with the actress' dance skills when he choreographed the ballet movie and is annoyed when people claim she used a double for most of the film.

He said: "It was so believable, it was fantastic, that beautiful movement quality. There are articles now talking about her dance double [American Ballet Theatre dancer Sarah Lane] that are making it sound like [Lane] did a lot of the work, but really, she just did the footwork, and the fouettes, and one diagonal [phrase] in the studio. Honestly, 85 per cent of that movie is Natalie."

Benjamin added Natalie - who won a Best Actress Oscar for the performance earlier this year - was not faultless and his choreography was key to allowing her to look like a ballet star.

Asked how it was possible to feature long unbroken shots of Natalie's dancing, he explained: "By making things fluid and not too complicated. By getting more movement going, which in turn added to the camera movement - that is basically what I did. If we had kept things more classical, more restrained, less fluid, it would have been harder to trick the eye."

However, although he says working with his fiancee was a "phenomenal" experience, Benjamin revealed he has no plans to work with her again.

He told the Los Angeles Times: "I mean I think this was a phenomenal, unforgettable experience. But there are no plans to collaborate again in the future."