The upcoming two-part erotic film is to feature graphic sex scenes between cast members, producer Louise Vesth told The Hollywood Reporter.
However, the real hardcore scenes will be filmed using body doubles, who will then be combined with the stars' non-explicit acts using digital technology, she explained.
Charlotte Gainsbourg, Stellan Skarsgard, Shia LeBeouf, Uma Thurman, Willem Dafoe, Christian Slater and Jamie Bell are among the film's cast.
"We shot the actors pretending to have sex and then had the body doubles, who really did have sex, and in post we will digital-impose the two," Vesth said.
"So above the waist it will be the star and below the waist it will be the doubles."
The post-production work on the project is said to be the reason why it was not available to be screened at Cannes this week.
Vesth continued to explain that von Trier has used experimental techniques in the film, including double exposures and utilising words and symbols over sequences.
One distributor who saw early footage of the film described it as "groundbreaking...like nothing [they've] ever seen".
Vesth added that she hopes von Trier will end his self-imposed ban on promotion, following his infamous Nazi remarks two years ago.
"Lars has thrown everything in this one," she said. "It's about religion, about God, about philosophy. There's so much to talk about with this movie. I hope he changes his mind and starts giving interviews again."
The world premiere will be held in Copenhagen, Denmark this December.