Actress Kristen Stewart is reportedly dating Nicholas Hoult, her co-star in upcoming movie "Equals".

The rumours went rife after Stewart was seen getting cosy with Hoult on the film's set, reports hollywoodlife.com.

"Kristen and Nick (Nicholas) are inseparable. They are constantly hanging out together when they aren't on set. They've really bonded with each other and are like best friends now. It wouldn't surprise any if us if it turns into something more serious, something romantic,` said a source.

"When Kristen is on location for long periods of time, she usually has a good friend come stay with her but not this time because she has Nick," the source added.

The rumoured couple also likes to play pranks on the film crew.

"They love playing practical jokes on the cast and crew, playing pool, just exploring and hanging out," said the source.