Prime Minister Junichiro Koizumi reiterated Thursday his determination to uphold the nation's antiwar pledge as he attended a memorial marking the 57th anniversary of Japan's surrender in World War II.

About 5,000 relatives of the war dead and 1,000 guests, including Emperor Akihito, Empress Michiko and leading figures from the public and private sectors, took part in the annual ceremony at Nippon Budokan Hall in Tokyo.

"This year marks the 50th year after the San Francisco Peace Treaty took effect and our country regained its sovereignty," Koizumi said.

He vowed to "adhere to the pledge for no war" and to make efforts to ensure that Japan, as a member of the international community, contributes to world peace by "improving relationships with neighboring countries."

As in his speech at the ceremony last year, Koizumi expressed "deep remorse" for "the tremendous damage and pain" Japan caused during the war, especially to people in Asia.

The annual ceremony is dedicated to the 3.1 million Japanese who died in the war, comprising 2.3 million service members and 800,000 civilians. The annual government-sponsored event was first held in 1982.

Most attendees were relatives of the war dead, according to the Health, Labor and Welfare Ministry. The oldest was Shizu Futamata, 94, from Aichi Prefecture, whose husband was an Imperial Japanese Army master sergeant when he was killed in combat in China in 1938.

Before attending the ceremony, Koizumi laid a wreath at nearby Chidorigafuchi National Cemetery for the unidentified remains of the war dead.

A year ago, Koizumi drew protests from leaders of China and South Korea when he visited Yasukuni Shrine on Aug. 13. The Shinto shrine honors members of Japan's military war dead as well as 14 wartime leaders convicted as Class-A war criminals by an Allied-led international tribunal.

Koizumi paid a visit to Yasukuni again in April but promised not to go again this year.

A government panel is discussing creation of a new memorial facility so political leaders can pay tribute without provoking neighboring countries or drawing controversy over the separation of state and religion.

However, Koizumi recently said the proposed facility would not be an alternative to Yasukuni, raising doubts over the plan launched by his own Cabinet.

On Thursday, five members of Koizumi's Cabinet, Tokyo Gov. Shintaro Ishihara and a group of Diet members paid tribute at Yasukuni.

The Cabinet members were Takeo Hiranuma, minister of economy, trade and industry; Defense Agency chief Gen Nakatani; Toranosuke Katayama, minister of public management, home affairs, posts and telecommunications; Jin Murai, chairman of the National Public Safety Commission; and Tsutomu Takebe, minister of agriculture, forestry and fisheries. Takebe also visited the shrine Aug. 6.

Ishihara visited the shrine for the third straight year.

About 180 members and representatives from a parliamentarians' group visited the shrine. The group pays tribute at Yasukuni every year on the surrender anniversary and during two festivals. Tsutomu Kawara, former Defense Agency chief and a Diet member from the ruling Liberal Democratic Party, heads the group.

It comprises Diet members from the LDP as well as the Democratic Party of Japan and the Liberal Party.