STORY: 'Captain America 3' to Challenge Batman-Superman Head On (Exclusive)

“It will be a further expansion of this universe,” Silverman said. “Superman vs. Batman will lead into Justice League.”

A release date has not been set, but sources say it could bow in 2017, a year after Superman vs. Batman, which is set to hit theaters May 6, 2016. The movies will be shot back-to-back. Warner Bros. declined comment on release plans.

Superman vs. Batman will feature many of the Justice League superheroes in cameos or supporting appearances. For example, last week, Ray Fisher, who is perhaps best known for portraying a young Muhammad Ali in the stage production Fetch Clay, Make Man, was revealed to be in negotiations to play Victor Stone, the promising football player whose life is derailed and is forced to become the hero known as Cyborg. He's slated to appear in only one scene, though that could change as the script is polished.

STORY: Zack Snyder: Movie Team of Superman, Batman and Wonder Woman 'Kind of Epic'

By confirming Snyder on a Justice League movie, the studio confirms an actual Justice League movie. The movie, which will collect all the big guns from the Warners-owned DC Entertainment, had been rumored as the goal but Warners was always mum on when, or in how many movies after Man of Steel, it would be reached.

And the Justice League movie should dampen, at least partially, the critics that have jabbed Warners for not having a superhero strategy like its rival, Marvel Studios, or for not adequately capitalizing on the intellectual property it owns.

Warner came close making a Justice league movie around 2008. George Miller, the filmmaker behind the Mad Max and Happy Feet films, had a cast in place when several factors – high budget, the WGA writers strike, among them – derailed it. At the time, Armie Hammer was slated to play Batman, Adam Brody the Flash, Common as Green Lantern, among others on the roll call.

The team, initially known as the Justice League of America, made its first appearance in Brave and the Bold #28. Three issues later, the team got its own title, which swiftly became DC's top comic. (The Avengers, Marvel's attempt to create their own version of a collection of its popular heroes, didn't appear until 1963.)