An alliance of civil groups from China and seven other countries is in the process of registering documents on Japan's use of war-time sex slaves with UNESCO's Memory of the World Register.

The records include photographs and tapes detailing the victims' experiences and the investigation process. Japan has issued objections to the process. In response, Chinese Foreign Ministry Spokesperson Hong Lei says the action will preserve history and serve as a reminder to the world of the atrocities of war.

"China urges Japan to treat the registering process of war-time sex slaves with fairness and honesty. Japan should fulfill its promises to deal with historical issues and win the trust of its Asian neighbors and the international community through concrete actions，" he said.