The speaker of South Korea's National Assembly has added fuel to a simmering controversy over his call for the Emperor to apologize to "comfort women," describing Japan as a "brazen thief" for demanding that he retract his comments.

The term "comfort women" is a euphemism used to refer to women who provided sex, including those who did so against their will, for Japanese troops before and during World War II.

In interviews with several South Korean media organizations reported Monday, Moon Hee-sang doubled down on his demand for an apology from Emperor Akihito to settle the long-standing dispute.