Kristen Stewart was "shocked" by the sex scenes in 'Twilight Saga: Breaking Dawn'.

The 21-year-old star's character Bella Swan gets intimate with vampire Edward Cullen - played by the actress' real-life boyfriend Robert Pattinson - in the final two movies in the franchise and Kristen found the raunchy experience "surreal".

She said: "There are two big sex scenes in the two final films and we did them fairly early. It was so weird, it didn't even feel like we were doing a scene within a 'Twilight' film.

"I was like, 'Bella! What are you doing? Wow! What is happening here?' It was very surreal."

Film censors ordered the scene to be re-cut as it was deemed too raunchy for their teen audience, but Kristen insists the intimate action was "tame".

She said: "We originally got rated R but they re-cut it.

"It was tame! I've done my share of coming-of-age movies and the ratings board know who our audience is and can be like, 'Hmm guys, just cool it a little.'

It's funny because in the book, you don't see anything, it's everyone's imagination, so it's entirely subjective. I hope it's good."