Ben Affleck traveled to Washington D.C. Thursday to offer testimony before the U.S. Senate about the importance of foreign aid in Africa, citing his philanthropic efforts in the Democratic Republic of the Congo, but he also stopped to reference his upcoming Batman film.

After thanking Senator Lindsey Graham (R-SC) for being a “genuine” champion for U.S. foreign assistance, Affleck turned his attention to Senator Patrick Leahy (D-VT), who has cameo role in the upcoming film Batman v Superman: Dawn of Justice:

“I would be remiss not to recognize my co-star in Batman,’” Affleck joked to Leahy. “Your role was marginally smaller than mine, but I understand you are quite good,” added the actor.

According to Page Six, Senator Leahy is a major Batman fan who’s appeared now in three of the franchise’s films, including Batman & Robin, The Dark Knight Rises, and a small voice role in an animated Batman series.

The Academy Award-winning actor and director was in Washington to speak before the Senate State, Foreign Operations and Related Programs Subcommittee, where he was joined by fellow philanthropist Bill Gates. Affleck thanked the panel, before describing Gates as: “The greatest and most important philanthropist in the history of the world.”

“Truly, It’s an honor to sit next to Mr. Gates, who has done such extraordinary things in technology and philanthropy,” he said.

Affleck then made an appeal for continued U.S. foreign assistance investments to drive economic development programs and make a lasting impact in the Democratic Republic of the Congo.

Affleck took to Instagram shortly after his testimony to share his philanthropic experiences:

While visiting Children’s Voice in Goma, I loved watching how excited the school children were to learn and succeed. In this part of #DRC, more than 42% of children have never been to school. #ECI ©2010 Barbara Kinney Photography

A photo posted by Ben Affleck (@benaffleck) on Mar 26, 2015 at 1:07pm PDT

Affleck is the founder of the Eastern Congo Initiative, which “envisions an Eastern Congo vibrant with abundant opportunities for economic and social development, where a robust civil society can flourish.”

Per the group’s website, ECI hopes to increase investments from both private and public funding sources to strategically support established Congolese-led programs that build safe and sustainable communities.

You can watch Affleck’s testimony in its entirety here.

Batman v Superman: Dawn of Justice is currently in post-production, and will be released in 2016.