Actress Natalie Portman has reportedly entered into negotiations to star in Alfonso Cuarón's new sci-fi project Gravity, according to Heat Vision Blog.

We reported earlier this month that Natalie Portman was offered the role by director Alfonso Cuarón, after Angelina Jolie passed on the project twice. Now it is being said that Warner Bros. and Natalie Portman are in "active negotiations."

Robert Downey Jr. is currently attached to star in the movie, although the role Natalie Portman would play is the centerpiece of the project. The story revolves around this lead female character's quest for survival after debris wipes out her space station's crew. The movie will be shot in 3D on an $80 million budget, according to our earlier report.

We'll be sure to keep you posted with any further information on Gravity as soon as we have it.