E! Online said Friday while Pitt and Jolie's attorney alleges Brett would violate a confidentiality agreement by writing about his time with the celebrity couple, Brett insists a memoir is still a possibility.
"I have not decided if I will write it or not yet," the former bodyguard said.
An April report by the New York Daily News said Brett's book would have less than positive information about Pitt, star of films like "Spy Game" and "Fight Club."
Martin Singer, who represents Pitt and Jolie, told the Daily News that Brett allegedly misrepresented himself as a former British commando and was once interviewed in relation to a murder investigation.
E! Online said in addition to working for Pitt and Jolie, Brett counts film stars Sandra Bullock and Tom Cruise among his past employers.
Copyright 2009 by United Press International.