Gervais has begun sketching out plans for a one-off episode of the BBC comedy series, potentially for Christmas 2009.
Mirroring Gervais' recent forays into US films such as the current release Ghost Town, his character, struggling actor Andy Millman, will try to make it big in Hollywood.
Gervais first mooted the idea in an interview with men's magazine Zoo earlier this week, but was concerned that Merchant would not want to do it.
However, writing on his blog today, he confirmed that the pair would collaborate on another episode.
“He's in LA at the moment but the story that went out across America was that, although I would consider it, I thought Steve would take some convincing,” Gervais wrote.
“Well I got an email today from him saying he's up for it. I started work on it immediately. Does anyone know Al Pacino?”
Extras, created by Gervais and Merchant, ran for two series on BBC2 and returned for a two-part Christmas special on BBC1 last year.