Do the british imitate American dialogue in their movies?

I wonder if they have any films where a british/english person is playing an american, and has to talk like an

american, and how common is it?. It always seems to be the other way around.Do the british imitate American dialogue in their movies?Alan Rickman, Catherine Zeta Jones, Emma Thompson, Miriam Margolyes, Hugh Laurie. They do a better job than Dick Van Dyke and his "Cor blimey Mary Poppins."Do the british imitate American dialogue in their movies?sean bean in silent hill. and clive owen in sin city (i think)