"The Pianist" star said he was not prepared to play a stereotypical role next to the digitally enhanced ape, reported imdb.com.
Brody was quoted as saying: "It's true that King Kong is the title character, but one of my problems with the original film is that you don't identify much with the story of the characters.
"You're just interested in the spectacle of the monkey. But I want to contribute some depth to it and something interesting."
Brody, 31, knew "The Lord Of The Rings" director would not have approached him if he simply wanted the Oscar winner to make up the human numbers in the film.
"I think Peter Jackson is going to create the definitive 'King Kong'. It will have a little more than the monkey to attract audiences and remain interesting to a full range of people," said Brody.