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.

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.

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.