Snyder surprised fans with the news this morning during a live online commentary of his film "Man of Steel" with Henry Cavill.
While Snyder is the credited director of 2017's "Justice League" the film was finished by director Joss Whedon prompting a social media fan initiative to #ReleaseTheSnyderCut.
"Well, the fans have asked, and we are thrilled to finally deliver," said Robert Greenblatt, Chairman, Warner Media Entertainment and Direct-To-Consumer.
"At the end of the day, it really is all about them and we are beyond excited to be able to release Zack's ultimate vision for this film in 2021," said Greenblatt. "This could never have happened if it weren't for the hard work and combined efforts of the teams at HBO Max and Warner Bros. Pictures."
"I want to thank HBO Max and Warner Brothers for this brave gesture of supporting artists and allowing their true visions to be realized," Snyder shared. "Also a special thank you to all of those involved in the SnyderCut movement for making this a reality."
"Justice League" represented the first time the superstars of the DC Universe were seen together in live-action on the big screen, and starred Henry Cavill as Superman, Ben Affleck as Batman, Gal Gadot as Wonder Woman, Jason Momoa as Aquaman, Ezra Miller as The Flash and Ray Fisher as Cyborg. It also gave DC fans their first cinematic taste of Jack Kirby's Fourth World with the appearance of Steppenwolf as the movie's villain.
In the movie, fueled by his restored faith in humanity and inspired by Superman's selfless act at the end of "Batman v Superman," Bruce Wayne enlists the help of his newfound ally, Diana Prince, to face an even greater enemy. Together, Batman and Wonder Woman work quickly to find and recruit a team of metahumans to stand against this newly awakened threat. But despite the formation of this unprecedented league of heroes - Batman, Wonder Woman, Aquaman, Cyborg and The Flash - it may already be too late to save the planet from an assault of catastrophic proportions.
In the two and a half years since "Justice League's" release, several of the movie's heroes have broken out with franchises of their own, including Momoa's "Aquaman" and Gadot's "Wonder Woman," the latter of whom will return to theaters later this year in "Wonder Woman 1984."