Speaking to MTV, the Oscar winner revealed that she would like to reprise her role as the assassin Victoria for the follow-up.
When asked what it would take for her to sign on for the movie, Mirren responded: "Nothing, just get me the script. You don't have to do anything. I'm there. Absolutely."
Loosely based on the WildStorm miniseries by Warren Ellis and Cully Hamner, RED arrived in theatres last October. Writers Erich and Jon Hoeber are currently working on a script for the sequel.
Writer Ellis previously told DS that he has no plans to pen a comic book sequel to tie in with the new movie.
A potential release window for the RED sequel is yet to be announced.