Actor Robert Pattinson wants to keep his relationship with ex-girlfriend Kristen Stewart "professional".

The 26-year-old actor will appear with his former co-star - who cheated on him with married Snow White and the Huntsman director Rupert Sanders – at the international premieres of the final instalment of the Twilight Saga because he wants to prove he can overlook her actions for the sake of his fans.

A source told The Sun newspaper: "It's a purely business decision. He's keen to make sure fans and Hollywood see he can be professional when it comes to Kristen."

However, the heartbroken Pattinson is still refusing to discuss the 22-year-old actress in interviews and wants to keep all press relevant to the film.

This comes after Stewart announced "we're going to be fine. We're totally fine," when she was quizzed about promoting The Twilight Saga: Breaking Dawn Part 2 with Pattinson in November.

She added: "We have been waiting for this thing to be unleashed for so long. It was sort of one of those situations where you just have to put yourself in your body and go appreciate the moment."

The former couple – who met while playing on-screen lovers Bella Swan and Edward Cullen in the sparkly vampire franchise – had been rumoured to have rekindled their romance, after it had been "communicated to people" during the Toronto Film Festival that they were back on.