Keira Knightley is filming a lesbian sex scene for her new movie.

The 'Anna Karenina' star - who recently got married to musician James Righton - will be seen passionately locking lips with 16-year-old actress Chloe Grace Moretz for the film 'Laggies', in which she plays a runaway bride.

A source told the Daily Star newspaper: "No one is talking about the physical scenes yet but Keira and Chloe will be seen together and there will be some lesbian love action. It's set to be very saucy and will definitely get male fans hot under the collar."

The 28-year-old newlywed is set to play a woman who runs away from home and develops a friendship with a group of teenagers after being caught off-guard by her boyfriend's marriage proposal.

Keira, who wed Klaxons musician James, 29, last month, was reportedly looking to take a break from Hollywood after her nuptials - but quickly jumped at the opportunity to star in the provocative film after Oscar winner Anne Hathaway quit the role.

The source added: "After getting married Keira turned down some major Hollywood scripts so she could enjoy married life. But she loved the script and was eager to jump on board when Anne Hathaway dropped out."

The steamy movie is the latest boundary-pushing role for Keira's co-star Chloe, who caused controversy in 2010 when she played foul-mouthed crime-fighter Hit Girl in violent flick 'Kick-Ass' aged just 13.