Japan's ministers bow during a memorial service marking the 80th anniversary of Japan's World War II defeat, at the Nippon Budokan hall on Friday in Tokyo. (AP Photo/Eugene Hoshiko)

TOKYO (AP) — Japan paid tribute Friday to more than 3 million war dead as the country marked its surrender that ended World War II 80 years ago, as concern grows about the rapidly fading memories of the tragedy of war and the bitter lessons from the era of Japanese militarism.

Prime Minister Shigeru Ishiba expressed “remorse” over the war — the first time a Japanese leader has used the word in a Aug. 15 address since former premier Shinzo Abe shunned it in 2013.

Ishiba called the war a mistake, but did not mention Japan’s aggression across Asia or apologize.

“We will never repeat the tragedy of the war. We will never go the wrong way,” Ishiba said. “Once again, we must deeply keep to our hearts the remorse and lesson from that war.”

He vowed to pass his peace pledge to next generations.

In a national ceremony Friday at Tokyo’s Budokan hall, about 4,500 officials and bereaved families and their descendants from around the country observed a moment of silence at noon, the time when Emperor Hirohito’s surrender speech began on Aug. 15, 1945. Participants later offered chrysanthemum flowers for the war dead.

Just a block away at the Yasukuni Shrine, dozens of Japanese rightwing politicians and their supporters gathered to pray.

The shrine honors Japan’s 2.5 million war dead, including convicted war criminals. Victims of Japanese aggression, especially China and the Koreas, see visits to the shrine as a lack of remorse about Japan’s wartime past.

Ishiba stayed away from Yasukuni and sent a religious ornament as a personal gesture instead of praying at the controversial shrine.

But Shinjiro Koizumi, the agriculture minister considered as a top candidate to replace the beleaguered prime minister, prayed at the shrine. He told reporters that he made the no-war pledge to the spirits. “It is important to not forget those who sacrificed their lives for their country,” he said.

Koizumi is the son of popular former Prime Minister Junichiro Koizumi, who outraged China when he visited Yasukuni as a serving leader in 2001.

Rightwing lawmakers, including former economic security ministers Sanae Takaichi and Takayuki Kobayashi, as well as governing Liberal Democratic Party heavyweight Koichi Hagiuda, also visited the shrine Friday.

A non-partisan group of 87 parliamentarians led by Liberal Democrat Ichiro Aisawa also prayed at Yasukuni, pledging “to uphold peace” in Japan and in the Indo-Pacific region.

Separately, Sohei Kamiya, head of the populist far-right Sanseito, prayed with 17 parliamentarians and 70 local assembly members from his party. He told reporters that the prime minister should visit Yasukuni.

Japanese emperors have stopped visiting the Yasukuni site since the enshrinement of top war criminals there in 1978.

Emperor Naruhito, in his address at the Budokan memorial Friday, expressed his hope that the ravages of war will never be repeated while “reflecting on our past and bearing in mind the feelings of deep remorse.”

Naruhito reiterated the importance of telling the war’s tragic history to younger generations as “we continue to seek the peace and happiness of the people in the future.”

As part of the 80th anniversary, he has traveled to Iwo Jima, Okinawa and Hiroshima, and is expected to visit Nagasaki with his daughter, Princess Aiko, in September.