TOKYO - Japanese Prime Minister Shigeru Ishiba on Monday sent a ritual offering to the notorious Yasukuni Shrine, a symbol of the country's past brutal militarism, on the occasion of its spring festival.

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

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He is not expected to visit the shrine in person during the festival, national broadcaster NHK reported.

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.

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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.