It's a sad morning for die-hard Robert Pattinson fans!

According to MTV, the "Twilight" actor has officially dropped out of "Parts Per Billion," a project he joined last December.

Apparently, Pattinson had to ditch the film because he's too busy prepping for "New Moon," the sequel to last year's big-screen vampire romance.

Starring Rosario Dawson, Olivia Thirlby and Dennis Hopper, "Billion" follows three couples who risk being torn apart after struggling with the same event. The film is described as an ensemble story with different storylines.

Pattinson quickly rose to fame after he got the role as Edward Cullen in the adaptation of Stephenie Meyer's popular book. Now his fans will have to wait a little longer until they get to see him in something other than a "Twilight" sequel.

"Twilight" star Robert Pattinson will join Rosario Dawson, Olivia Thirlby and Dennis Hopper in "Parts per Billion," according to MTV.

Brian Horiuchi is directing the film, which follows three couples who risk being torn apart after struggling with the same event. The film is described as an ensemble story with different storylines.

Pattinson had been in the media spotlight ever since he signed on to star in "Twilight." He's already on board for "New Moon," although he will shoot "Parts per Billion" first.

During her interview with MTV, Dawson said she's excited to meet and work with Pattinson, although their characters never really meet in the film.

By the way, did you catch the trailer for Pattinson's other flick, "Little Ashes"? Click here if you missed it.