Former U.S. Vice President Joe Biden on Wednesday refused to apologize for comments about his dealings with two segregationist senators in the 1970s, and said that Sen. Cory Booker and other critics among his Democratic rivals were being disingenuous.

"Apologize for what? Cory should apologize. He knows better," Biden said at a Maryland fundraiser. "There's not a racist bone in my body, I've been involved in civil rights my whole career. Period. Period. Period."

Biden was responding to criticism from Booker, who had demanded that he ask forgiveness for saying that he was able to work with segregationists in an atmosphere of "civility" in the U.S. Senate more than four decades ago.