ABC News chief anchor George Stephanopoulos has given $50,000 to the Clinton Foundation in recent years, charitable contributions that he did not publicly disclose while reporting on the Clintons or their non-profit organization, the On Media blog has learned.

In both 2013 and 2014, Stephanopoulos made a $25,000 donation to the 501 nonprofit founded by former president Bill Clinton, the Foundation’s records show. Stephanopoulos never disclosed this information to viewers, even when interviewing author Peter Schweizer last month about his book “Clinton Cash,” which alleges that donations to the Foundation may have influenced some of Hillary Clinton’s actions as Secretary of State.

In a statement to the On Media blog on Thursday, Stephanopoulos apologized and said that he should have disclosed the donations to ABC News and its viewers.

“I made charitable donations to the Foundation in support of the work they’re doing on global AIDS prevention and deforestation, causes I care about deeply,” he said. “I thought that my contributions were a matter of public record. However, in hindsight, I should have taken the extra step of personally disclosing my donations to my employer and to the viewers on air during the recent news stories about the Foundation. I apologize.”

Stephanopoulos is the chief anchor and chief political correspondent for ABC News, as well as the co-anchor of ABC’s “Good Morning America” and host of “This Week,” its Sunday morning public affairs program. Prior to joining ABC News, he served as communications director and senior advisor for policy and strategy to President Clinton. He also served as communications director on Bill Clinton’s 1992 presidential campaign.