Sylvester Stallone thinks Arnold Schwarzenegger is better at comedy than him.

The action movie legends - who are also close friends - have reunited for 'Escape Plan', and when it comes to injecting humour into their roles, Stallone believes his co-star is the best.

Stallone said: ''I have to defer to Arnold on this one because he really developed action comedy and the use of humour in very dramatic situations. My characters? Rambo isn't exactly a barrel of laughs, is he?

''He invented the one-liner. 'I'll be back!' that's one of his major contributions. They didn't have those before.''

Schwarzenegger remains modest about his comedic chops, but particularly enjoyed acting goofy for one particular scene in the new movie.

He added to Nuts magazine: ''There's one very intense moment where I'm getting busy with a big gun wiping out all the bad guys' guards on the top of the prison but I've got my smirk on my face and a real deadpan line to deliver.''