Seoul's government expressed deep regret over Japanese Prime Minister Shinzo Abe's decision to send a ritual offering to the controversial Yasukuni Shrine on Thursday.
Tokyo's Chief Cabinet Secretary Yoshihide Suga said the PM made the offering in his capacity as a private citizen, but did not visit the shrine in person.
It's the 7th straight year Abe has sent offerings to mark the country's 1945 surrender in World War Two.
About 50 right-wing lawmakers from ruling and opposition parties also paid their respect at the shrine en masse.
The shrine honors Japan's war dead including 14 Class-A war criminals.
For Korea and China, it's regarded as a symbol of Japan's past imperialism and Abe faced a strong backlash for visiting the shrine in 2013.