The Twilight actress shows off her body

Kristen Stewart has been spotted wearing just her underwear while filming a saucy swimming scene for new movie Sils Maria.

The Twilight star stripped to a black bra and white shorts to take a dip in a lake in Switzerland with co-star Juliette Binoche, who bravely went completely nude.

Kristen, 23, was seen giggling as she tentatively entered the water.

When she emerged her shorts were soaked through, giving a glimpse of her skimpy black thong underneath.

According to Perez Hilton, K-Stew plays the ‘sexually ambiguous’ assistant of Juliette’s character in the movie and the two embark on a lesbian relationship.

Meanwhile, Kristen‘s ex Robert Pattinson, 27, has been hanging out with Dylan Penn at music venues.

When Kristen heard Rob had taken Dylan Penn out to listen to some music, she was not happy,’ a friend of K-Stew’s tells Hollywood Life.

She doesn’t understand what’s going on with Rob and his decision making. There are a million people Rob could date, but he picks someone like Dylan, someone Kristen knows.

Kristen is doing a lot better, but she still misses Rob and music was their thing, their bond.’

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Anna Francis