The long-awaited sequel to the science fiction epic Avatar from famed Canadian director James Cameron will require a little more patience from fans — three-and-a-half years to be exact.

According to the movie's official Facebook page, the next Avatar film will open in theatres Dec. 18, 2020. It's one of four upcoming films in the franchise.

"Avatar takes flight as we begin concurrent production on four sequels," the post reads alongside a birdseye photo of the crew involved in the project.

Following the first sequel, the next one will be released a year later, on Dec. 17, 2021.

The franchise will take a three-year break before returning to the screen with two more installments, on Dec. 20, 2024 and Dec. 19, 2025 respectively.

Avatar was the first film to gross more than $2 billion US when it was released in 2009 and earned nearly $2.8 billion worldwide.

The story is set in fictional Pandora, a resource-rich environment which future humans are trying to colonize. It's inhabited by the blue-skinned humanoid species, Na'vi, under threat from the expansion.

The original starred Sam Worthington, Zoe Saldana and Sigourney Weaver.

The first sequel had been expected in 2018 but Cameron, who was also behind the 1997 Oscar-winning film Titanic and sci-fi thrillers such as The Terminator and Aliens, said earlier this year that wasn't going to happen.

Cameron initially told the Toronto Star in March about the delay, but said the scripts were done for all four Avatar films. The director called it "an epic undertaking" "not unlike building the Three Gorges Dam."