The second half of 'The Twilight Saga: Breaking Dawn' does not have a release date.

The concluding film in the movie franchise - which stars Robert Pattinson as a vampire who falls in love with human Bella Swan (Kristen Stewart) - was set for a release in summer 2012, but now a studio executive has revealed no date has been confirmed.

Richie Fay, distribution chief at production company Summit Entertainment, revealed: "We've targeted a number of dates, and we have yet to determine when it will happen. We haven't even determined that it will be the summer. It's still the source of discussions."

With 'Twilight' movies having been released in both the summer and autumn, Fay advised Summit may wait to see how successful current instalment 'Eclipse' is in the box office before making a final decision on the film's release date.

He told MTV News: "We might have a preference when we see where 'Eclipse' ends up. It certainly might colour our thinking, but we're comfortable with either place. Right now, it's a bit early in that stage of planning."

Screenwriter Melissa Rosenberg recently explained splitting the fourth movie may be a difficult task.

She stated: "When we started, everyone was a little bit unsure. It kind of came down to me looking at the book and going, 'Are there two movies in this?'

"We all wanted it to be two movies. Then it came down to, 'Are the actors available for two movies?' So there was a lot of things that went into this decision."