Japan will go ahead with a memorial ceremony on Sunday near the Sado Island Gold Mines, despite South Korea’s last-minute boycott of the event that highlighted tensions between the neighbors over the issue of Korean forced laborers at the site before and during World War II.

South Korea says it will not attend a ceremony in Japan to commemorate victims of forced labor in the Sado Island Gold Mines. This comes as the two nations seek to draw together amid regional threats.

North Korea condemned on Saturday recent joint military drills by the United States, South Korea and Japan, warning that it would take immediate actions if needed to defend the state. Last week, the three countries held a three-day joint exercise,

South Korea’s government says it has decided not to attend a memorial service near Japan’s Sado Island Gold Mines due to unspecified disagreements with Japan over the event, which stirred longstanding tensions over the abuse of Korean forced laborers at the site before the end of World War II.

Japan will hold a memorial ceremony near the Sado Island Gold Mines, which were listed this summer as a UNESCO World Heritage site after the country moved past years of disputes with South Korea and reluctantly acknowledged the dark side of their history.