Harry Hill thinks Julie Walters is funnier than him in 'The Harry Hill Movie'.

The comedian has bagged an all-star British cast, including the BAFTA-winning actress and Matt Lucas, for his feature film debut but admits it was tough having so many funny stars on set as he had to step up his own comedy game to compete with his co-stars.

Speaking exclusively to BANG Showbiz at the UK premiere of 'The Harry Hill Movie' in London's Leicester Square on Thursday (19.12.13), he said: ''The problem I've got is hiring all these really funny people is, I've made a real job for myself to try and be the funniest person in the film.

''Actually, the funniest person in the film is Julie. Often I would look round and she'd be pulling a funny face or doing a funny walk.

''She's the naughtiest. Although she's older than me, she's like a little girl. She's got this really kind of impish spirit about her.''

Hill had such a good time making the slapstick film he would love to turn it into a comedy franchise like the quintessential British movie series, 'Carry On'.

He added: ''Obviously, having done this one, it's given me loads of ideas because it's such a great team and I think if we could get the same cast and make another film in the same way as those 'Carry On' films ... if you could get the same gang and make a different story each time and all play different parts.''

Other stars who attended the premiere include Julie Walters, Sheridan Smith, Jim Broadbent and Johnny Vegas.