Reynolds would, of course, return to star in the film; although no deal has been made as yet. And it's reported that the studio is 'keen' on having Washington come back as well.
One problem though (and this is going to be a *spoiler* for anyone who hasn't seen the film yet), Washington dies at the end of the first film. So if they do get him back for the sequel, how will they pull that off?
The most likely way, of course, is to make the film a prequel; but then again, how would that work, since the characters Washington and Reynolds play in the film have never met before when the film begins.
However, I can completely understand Universal's desire to have Washington back in the sequel since Ryan Reynolds alone probably couldn't carry the film.