Vaughn will reunite with Bryan Singer, who will continue to serve as producer for the sequel, reports Deadline.
In November, Simon Kinberg signed on as a writer for the sequel.
Kinberg was a writer and producer on X-Men: The Last Stand, the third and final instalment of the original X-Men trilogy.
Watch X-Men: First Class star Jason Flemyng discuss the sequel with Digital Spy below:
James McAvoy previously spoke of his enthusiasm at reprising his role as Charles Xavier in future X-Men films.
McAvoy explained: "Ideally you have a story arc that lasts three movies and at the end of the third it leaves you ready for the story in X-Men 1. It would be nice to explore things in two more films. In this one, Magneto has gone through his major metamorphosis; he kind of found himself."