Testifying Thursday on Capitol Hill, actor Ben Affleck reminded senators that, well, he's Batman -- and dropped a minor spoiler about the upcoming Warner Bros. film.

“To Senator Leahy, I would be remiss if I did not acknowledge my co-star in Batman," Affleck said, addressing Sen. Patrick Leahy of Vermont. "The role is marginally smaller than mine but I understand you're quite good.”

It was confirmation that Leahy, a longtime Batman fan, will appear in next year's Batman v Superman: Dawn of Justice. Although the senator had been tight-lipped about his potential involvement, it's not really a surprise; after all, he's had cameos in 1997's Batman an Robin, 2008's The Dark Knight and 2012's The Dark Knight Rises. He also lent his voice to a 1995 episode of Batman: The Animated Series.

Affleck testified alongside Bill Gates before the Senate Appropriations Subcommittee on Diplomacy and National Security about the situation in Congo. The actor/director co-founded the Eastern Congo Initiative in 2010.

. @BenAffleck & Patrick Leahy discuss foreign aid impact (& #Batman ) before today’s hg. pic.twitter.com/KL6i15XskE— Sen. Patrick Leahy (@SenatorLeahy) March 26, 2015