TOKYO, Oct. 17 (Xinhuanet) -- Leaders of Japan's opposition parties criticized Prime Minister Junichiro Koizumi for his visit to the Yasukuni Shrine on Monday.

    "It is very regretful. Since the Osaka High Court has ruled that the visits are unconstitutional, I hope (Koizumi) can cautiously deal with the issue in view of the principle of the separation of state and religion," said Seiji Maehara, president of the largest opposition party -- Democratic Party of Japan.

    The visit was also questioned by Koizumi's ruling partner. Takenori Kanzaki, leader of the New Komeito party, said that he felt really regretful about Koizumi's act although his party had repeatedly asked Koizumi to refrain from visiting the shrine.

    He said the issue would have impact on the alliance though the relationship would not be broken.

    Kazuo Shii, chairman of the Executive Committee of the JapaneseCommunist Party, pointed out that Koizumi's premiership and responsibility should be subject to questioning due to his practice.

    "It is an intolerable attitude of the premier to ignore the Osaka High Court's ruling and challenge the constitution," he said.

    Seiji Mataichi, secretary general of the Social Democratic Party, said his party will lodge a protest over the worship, and it is a very serious issue that Koizumi tramples on the constitution. Enditem.