Gerard Butler loves cake.

The actor forced himself to watch footage of Robert De Niro in 'Taxi Driver' to motivate him to work on his physique and cut out his favourite calorific treats in preparation for a nude scene in 'Law Abiding Citizen'.

He said: "There is definitely a lot of pressure for me to look a certain way and I'm not the kind of guy who always stays in shape.

"For this one I was inspired by De Niro in 'Taxi Driver' because you see him doing those press ups and straight away you know so much about this guy. That's the only thing that got me back into training and back looking cut again.

"But it was hard because I love my cupcakes so my trainer constantly had to chase me around!"

Gerard - who toned up for his role as a Spartan warrior in '300' - has previously admitted he goes "crazy" when he has to lose weight for a role.

He said: "I want to eat my potatoes and french fries and sponge cakes.

"When I play a role where I have to look good and I can't have my carbs it makes me crazy!"