SEOUL - South Korean President Park Geun-Hye on Sunday repeated a call for Japanese leaders to apologise to former wartime sex slaves, warning that "time is running out" for Tokyo.
Mainstream historians say up to 200,000 women, mainly from Korea but also from China, Indonesia and other Asian nations, were forced into sexual slavery for Japanese troops during the World War II.
The issue - a key sticking point in ties between the two neighbours - further strained relations in recent months amid an increasingly aggressive campaign in Japan to claim these "comfort women" were common prostitutes.
Park has urged Japanese leaders to offer an apology, and on Sunday repeated the call for Tokyo to use "all means" to resolve the issue as the number of survivors rapidly dwindles.
"We now have only 53 survivors, aged nearly 90 on average. Time is running out to restore their honour," Park said in a speech marking the anniversary of the country's 1919 uprising against the 1910-1945 Japanese colonial rule.
The victims have not been given redress for their treatment despite repeated efforts in the decades since the war.
Japan issued a landmark apology in 1993 - known as the Kono Statement.
But a tranche of the political right, including Prime Minister Shinzo Abe, still claim the wartime army brothels were staffed by professional prostitutes.
Tokyo also embarked on a global campaign to promote more sympathetic version of Japan's wartime atrocities in school textbooks.
Such efforts to "distort" the history also hurt relations, Park said.
Seoul-Tokyo ties have been icy for years since a long-running territorial row flared up and exacerbated other long-standing historical disputes.
Abe and Park have never met for a formal summit since they took power in 2012 and 2013 respectively, raising concerns over the partnership between the two main US military allies in Asia.