By Piya Sinha-Roy

SAN DIEGO (Reuters) - "Superman" director Zack Snyder said on Saturday that a sequel to last month's hit film was not only in the works, but would feature two of DC Comic's best-known caped crusaders - Superman versus Batman.

Snyder, who directed British actor Henry Cavill as Superman/Clark Kent, surprised the audience with the news at the end of a Warner Bros. film panel at San Diego's Comic-Con, an annual comics convention, and received thunderous applause from the 6,000-plus in attendance.

The sequel to the latest Superman film, "Man of Steel," is banking on the success of recent comic-book films that have paired up heroes from the comic book universe, such as Disney's Marvel superhero ensemble "The Avengers" in 2012, which made $1.5 billion at the worldwide box office.

The most recent installment of the Batman franchise, 2012's "The Dark Knight Rises," directed by Christopher Nolan and starring Christian Bale, has made more than $1 billion at the global box office.

"Superman" has not always seen success at the box office and 2006's sequel starring Brandon Routh did not perform up to industry expectations.

But Snyder's darker reimagining of the complex superhero in June's "Man of Steel" delivered a strong performance at the box office with $621 million worldwide. With Nolan as executive producer of the film, rumors were circulating that a pairing of Batman and Superman could come to the big screen.

Cavill is expected to reprise the role of Superman but there was no word on who would play Batman. Bale has previously shot down rumors that he would play the masked hero again.

Warner Bros., a unit of Time Warner Inc, showcased a number of upcoming films on Saturday at Comic-Con, including "Seventh Son," "300: Rise of an Empire," "Godzilla" and "The Lego Movie," which will bring together Superman and Batman in animated Lego form.

(Reporting by Piya Sinha-Roy; Editing by Mary Milliken and Eric Beech)

[Director Snyder poses for pictures after his arrival to the Australian premiere of "Man of Steel" in central Sydney (REUTERS)]