Japan's prime minister expressed deep regret over the suffering his country inflicted on Asian countries during World War II in a solemn ceremony Saturday that marked the 64th anniversary of Tokyo's surrender.

Prime Minister Taro Aso joined some 4,800 bereaved families to pay respect to 3.1 million Japanese war dead — 2.3 million soldiers and 800,000 civilians — at the Nihon Budokan hall in Tokyo. Emperor Akihito and Empress Michiko also attended the ceremony, leading a one-minute silence at noon.

"Our country inflicted tremendous damage and suffering on many countries, particularly people in Asia. As a representative of the Japanese people, I humbly express my remorse for the victims, along with deep regret," Aso said in a speech at the nationally televised ceremony.

The prime minister vowed that Japan would never repeat the tragedy.

Emperor Akihito — whose father Hirohito announced Japan's surrender in a radio broadcast on Aug. 15, 1945 — said he hoped Japan would never again wage a war.

"I mourn for those who died in the war and pray for world peace and further development of Japan," the 75-year-old emperor said in a speech.

Before the ceremony, Aso laid flowers at the secular Chidorigafuchi National Cemetery, where the remains of victims of World War II are laid to rest.

The prime minister did not attend a controversial war shrine located near the national cemetery. Yasukuni Shrine honors 2.5 million Japanese soldiers who died in wars from the late 1800s until 1945, including convicted war criminals.

Pacifists and the victims of Japanese aggression abhor Yasukuni as a glorification of past militarism and a symbol of Japan's conquest in Asia, including the invasion and occupation of China and Korea.

From 2001 to 2006, then Prime Minister Junichiro Koizumi's repeated visits to Yasukuni strained relations with China and South Korea, who denounced the act as a sign that Japan had failed to fully atone for invasions and atrocities.

Koizumi again visited the Yasukuni Shrine on Saturday. Former Prime Minister Shinzo Abe and some 40 lawmakers also went there. Of 17 ministers in Aso's Cabinet, only Consumer Affairs Minister Seiko Noda went to the shrine.

At the shrine, 50 white doves were set free. Former war veterans peacefully marched.

"The memory of the war is fading. So I am trying very hard to pass the story of our generation to the younger generation," said 82-year-old former naval officer Shiratake Kuribayashi.