The makers of the film have registered the title 'Days Of Future Past' with the Motion Picture Association of America (MPAA), reported E! online.
The storyline switches between the present day and a future in which mutants are an outlawed species, following the assassination of Senator Kelly by villain Magneto (Michael Fassbender).
Simon Kinberg, who also worked as a screenwriter on "X-Men: The Last Stand" will write the script while Matthew Vaughn will once again direct.
The director said that for the sequel he would only bring in one new character.
"We will only have one more new character. I won't say who he or she is! But we will only be bringing one more new character in. Because, I think, as Professor X (James McAvoy) is in a wheelchair, Magneto needs to have a nemesis he can fight with. Someone that will be his equal. I know who it is. It would be nice if I could say something, but I can't," Vaughn said.
