U.S. Ambassador to Korea Sung Kim on Thursday said Japan's drafting of women as sex slaves for troops during World War II was "a grave human rights violation."
"We very much hope that the Japanese leadership addresses this important issue in a way that eases the pain of the victims," he added.
Kim was speaking at a forum hosted by the Kwanhun Club, a fraternity of senior journalists, in Seoul. The U.S. ambassador was asked whether he agrees with Foreign Minister Yun Byung-se, who delivered a keynote speech at the UN Human Rights Council in Geneva, Switzerland on Wednesday where he referred to atrocity as the "the forgotten holocaust."
"Yes, I agree," Kim said. Although he stressed that the issue needs to be resolved by Seoul and Tokyo, he said the U.S. would "encourage the leadership of the two countries to address the issue in a way that satisfies concerns and eases pain."
However, Kim voiced support for Japan's right to so-called collective self-defense, which would allow it to deploy troops abroad if an ally is in some way under threat. Kim said the Tokyo-Washington alliance is as important to the U.S. as the Seoul-Washington alliance and any measure that reinforces that alliance is "positive."
The U.S. ambassador stressed that trilateral cooperation between South Korea, the U.S. and Japan is "strategically very important."
Although U.S. President Barack Obama would not act as a "mediator" between South Korea and Japan, relations between the two regional neighbors would be included on the agenda of talks between Obama and President Park Geun-hye in April.
Regarding North Korea's nuclear weapons, Kim said Pyongyang would have to show a clear willingness to dismantle its weapons if the six-party talks are to resume.