Natalie Portman & Mila Kunis Talk 'Black Swan' Sex Scene (VIDEO)

They made it look easy on the big screen, but stars Natalie Portman and Mila Kunis had a hard time filming their buzzed about sex scene in 'Black Swan.'

Walking the red carpet, Portman said that doing a sex scene with a friend made it, "more awkward," while Kunis had the most trouble with the crowd of onlookers.

"It's hard to have a sex scene, period. It doesn't matter if it's a friend, a male, a female," she told reporters. "You're with 100-something crew members, lighting you, repositioning you, there's no comfort whatsoever."

The love scene wasn't the only difficult part about the film -- both actresses lost considerable weight while in rigorous training for the demanding ballet scenes.

"I still have scars on my feet," Kunis told a reporter, while Portman revealed that she broke multiple ribs while in training.

To see a preview of their sex scene -- including a kiss shared between the two -- watch the trailer for the movie.

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