Pattinson 'to watch over Stewart on Road'

Robert Pattinson is reportedly worried because his rumoured girlfriend Kristen Stewart has to act out a number of sex scenes in On The Road.

Pattinson allegedly intends to stay on set to ensure that the sequences stay professional but the actress has warned him not to.

A source told Hollywood Life: "Rob plans on being on the set of On the Road, not because he has a role in the drama, but because Kristen has a real risque part!

"There are a lot of sex scenes including a threesome, and Rob wants to make sure that it's all pretend from the start and finish of the film."

The insider added: "He's very jealous. Kristen told him she didn't want him on the set because it would make her feel uncomfortable, but Rob said he's going to be there.

"Especially now that her scenes are with Viggo, who is very. very hot! Rob is free until filming begins on the next Twilight film, so he's got all the time in the world to keep an eye on Kristen - and he will."