http://www.telegraph.co.uk/culture/film/film-news/6931166/Avatar-fans-promised-alien-sex-scene-on-DVD.htmlThe sex scene was cut from the cinema version of James Cameron's 3D sci-fi adventure which is close to taking $1 billion (£621m) at the worldwide box office.
It features the giant blue avatar of paraplegic US Marine Jake Sully locking hair with his love interest, Neytiri.
Cameron said: "We had it in [the movie] and we cut it out so that will be something for the special edition DVD – if you want to see how they have sex."
Actress Zoe Saldana, who plays Neytiri, said the sex involves the same process the alien race uses to communicate on its fictional home planet.
In the film, communication takes place by locking hair with flora and fauna, in a process known as "synching."
Saldana said: "If you sync to your banshee and you're syncing to a tree, why not sync into a person?
"It was a very funny scene to shoot because there were so many technical things that sometimes you have to keep in mind that paying attention to all those might disrupt the fluidity of how a scene is supposed to take place."
The actress said the scene was left out originally because the film was aimed at a family audience.