TOKYO - South Korea on Thursday expressed regret over Japanese leaders sending offering to the notorious war-linked Yasukuni Shrine, seen as a symbol of the militaristic and colonial past of Japan.

Japanese Prime Minister Shigeru Ishiba sent a ritual offering under his name as prime minister on the occasion of the shrine's autumn festival, according to his office on Thursday.

South Korea's foreign ministry said in a statement that the government expresses deep disappointment and regret over the fact that responsible leaders of Japan once again sent offerings to or visited the Yasukuni Shrine, which glorifies Japan's war of aggression and enshrines war criminals.

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The ministry urged leaders of Japan's new cabinet to squarely face history and demonstrate through action their humble reflection and sincere remorse for Japan's past acts, noting this will become an important foundation for the establishment of future-oriented South Korea-Japan relations based on mutual trust.

Ishiba had sent a ceremonial tree, called "masakaki," on the first day of the three-day ceremony at the shrine located in central Tokyo's Chiyoda district.

This is the first time that Ishiba made such an offering since taking office on Oct 1. He is unlikely to visit the shrine during the festival, local media cited sources close to him.

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For a long time, some Japanese politicians and members of parliament have insisted on visiting the shrine, which has been strongly opposed by many peace-loving people at home and abroad.

The Yasukuni Shrine honors 14 convicted Class-A Japanese war criminals from World War II, including Hideki Tojo. It has long been a source of diplomatic friction for Japan and its neighbors.