Prime Minister Shinzo Abe on Wednesday warned South Korea that it risked damaging ties by dissolving a foundation set up as a key pillar of a 2015 bilateral agreement with Tokyo to settle the issue of Korean "comfort women" forced to provide sex for Japanese troops before and during World War II.

The agreement, under which Japan provided ¥1 billion (about $8.8 million) to the foundation to help former comfort women and their families, has been deeply unpopular in South Korea.

Japan-South Korea ties have long been strained over historical grievances related to Japan's 1910-1945 colonial rule of the Korean Peninsula.