GENEVA (Reuters) - Japan formally complained on Monday after South Korea’s foreign minister raised the issue of wartime “comfort women” at the top U.N. rights body, while warning that it should not be allowed to harm bilateral relations at a critical time in east Asia.

U.N. Secretary-General Antonio Guterres greets Kang Kyung-wha, South Korea's Foreign Minister, at the Human Rights Council at the United Nations in Geneva, Switzerland February 26, 2018. REUTERS/Denis Balibouse

“Comfort women” was Japan’s euphemism for Asian women - many of them Korean - forced to work in its wartime brothels. Under a 2015 deal, Japan apologized to the women and provided a 1 billion yen (now $9.4 million) fund to help them, but South Korea has recently sought to revisit the issue.

The two U.S. allies, who share a bitter history including Japanese colonization, are key to international efforts to rein in North Korea’s nuclear and missile program.

Kang Kyung-wha, foreign minister of South Korea, did not name Japan directly in her speech to the United Nations Human Rights Council, but called for a “victim-centered approach” to the issue of comfort women.

Kang said that the victims, now women in their 80s and 90s, were “still striving to restore their dignity and honour”.

“My government has humbly acknowledged that previous efforts to resolve the issue had clearly lacked a victim-centered approach...my government will take steps to help heal their scars and restore their dignity and honour,” Kang said.

Junichi Ihara, Japan’s ambassador to the U.N. in Geneva, asked about the call for a victim-centred approach, told reporters: “That is her assessment of their approach.”

“Japan is of the view that Minister Kang Kyung-wha’s bringing up the issue in her statement this morning is totally unacceptable and I myself conveyed our position to (South Korea’s) permanent representative here,” he added.

A 2015 bilateral agreement had confirmed that the issue was resolved “finally and irreversibly”, even if a government changes - as it had with the election of South Korean President Moon Jae-in last year - Ihara said.

Some 70 percent of the 47 former South Korean comfort women still alive at the time of the pact had received support from the fund, he said. “Atonement money” had also been provided to former comfort women in the Philippines and Taiwan.

“In view of the importance of our bilateral relations for peace, prosperity and stability in east Asia and beyond, the two countries also have a responsibility to the international community to steadily implement the agreement,” Ihara said.

Kang, in her speech, said that North Korea must heed the call by major powers to abandon its nuclear and ballistic missile programs and allow peace to take root on the divided peninsula.

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