No expense will be spared for the upcoming sequels of James Cameron's "Avatar" franchise, as the movies start their production with a reported billion-dollar budget.

Executive Chairman of 21st Century Fox Lachlan Murdoch revealed that the budget for "Avatar" sequels has reached more than one billion dollars. Murdoch has not yet disclosed a specific amount, but each movie is estimated to cost at least $250 million, a few million dollars less than their predecessor's $265-million budget. This means that the sci-fi franchise may become the most expensive back-to-back film production, dethroning Peter Jackson's "The Hobbit" trilogy, which cost an estimated total of $623 million.

The Collider suggested that movies with this kind of budget mostly rely on international reception from audiences, like F. Gary Gray's "The Fate of the Furious," which supposedly cost $250 million as well. The eighth installment of the action film franchise generated a box office revenue of only $225 million in the US theaters. Internationally, however, it grossed about a billion dollars, making the venture worth it for the producers of the film.

That said, the first installment of the sci-fi franchise made over two billion dollars worldwide. Thus, it is expected that all four upcoming movies will theoretically get the same reception and viewership from international audiences.

Screen Rant also assumed that the movies would maintain their momentum due to the track record of director Cameron. The director has arguably delivered on his movies and their sequels, the latter being relatively harder to achieve.

Cameron is also no stranger to working with a huge budget, as evident in one of his past movies, "Titanic," whose production expenses exceeded the initial budget. The famous Leonardo DiCaprio and Kate Winslet romance film was made with $200 million. Adjusted for inflation, it remains among the top five most expensive movie ever created.

"Avatar 2" is set to arrive in theaters on Dec. 18, 2020.