Korea-born member of the U.S. House of Representatives Young Kim has criticized a Harvard law school professor's recent claims that Japanese military sex slaves during World War Two were willing prostitutes. 

Kim, a Republican Representative from California, in a Twitter post on Thursday called Professor John Mark Ramseyer's claims "untrue, misleading and disgusting."

Kim said that she worked on 'comfort women' issues for years and that Ramseyer's comments are offensive to victims. 

She added that people must support victims of human trafficking and slavery, not tear them down, urging the Harvard professor to apologize. 

Ramseyer sparked controversy in a recent article titled, "Contracting for sex in the Pacific War”, in which he describes the wartime forced sex slavery organized by Japan as a "consenting, contractual process" where women could negotiate for wages.