Robert said he is committed to starring in the final outing to date, but doesn't know when backers Summit Entertainment will begin production because of the actor's jam-packed shooting schedule.
Robert, who turned 23 last week, will be shooting his final days of "New Moon" in Italy on Friday.
"You're playing a figment in Bella's imagination so I was trying to do it in a 2-D way. I hope it doesn't translate onscreen as being boring," Robert said.
The vampire franchise has catapulted Robert's career – and it isn't slowing down anytime soon.
Robert will take a few days off after finishing "New Moon" before starting the filming of "Remember Me," a drama about two lovers.
After the eight-week shoot for "Remember Me," Robert will take three days off before finishing the third "Twilight" movie, "Eclipse," in October.
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PLAY IT NOW: Dish Of Salt: Peter Facinelli Talks 'New Moon' (May 11, 2009)