Sienna Miller has been caught kissing her co-star James Franco.

The actress - who is reportedly back with on-off boyfriend Jude Law - was photographed locking lips with the "Spider-Man" star in Toronto, Canada, last weekend.

Onlookers said the pair - who are in the Canadian city filming black comedy "Camille" together - looked "very into each other" as they took in a movie, concert and dinner.

It is not the first time Franco, 28, and "Alfie" star Miller have been caught getting close in public.

The pair also spent a day shopping together and the actor was seen "touching her hair".

Earlier this year, Miller was linked to another co-star, Hayden Christensen.

However, the actress' fling with the "Star Wars" star - who appeared alongside her in upcoming movie "Factory Girl" - ended abruptly in April when she dumped him and flew to Los Angeles to try and patch things up with Law.

The British actor and Miller - who have had an on/off relationship since Jude admitted sleeping with his children's nanny last year - were recently spotted on a night out with friends in Hollywood.

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