Japanese Prime Minister Shinzo Abe sent a message to an April memorial service dedicated to World War II war criminals, organisers said Wednesday, in a move that prompted a scolding from China.

In the ceremony organised by former Japanese military officers, some 220 people prayed before a cenotaph on which the names of around 1,180 suspected and convicted World War II war criminals are inscribed, organisers said.

They include 14 "Class A" war criminals, who are also enshrined at the controversial Yasukuni Shrine, a spot seen in mainland Asia as a symbol of Japan's past aggression.

The service took place on April 29 at a temple in Wakayama prefecture in western Japan, and the master of the ceremony read the message from Abe, an organiser told AFP.

In his message, Abe said: "I express my grief at the death of martyrs... who sacrificed their lives to form the foundation of peace and prosperity in Japan today," according to two participants and a report by the Asahi Shimbun newspaper.

"I pledge to work towards the future harmonious coexistence of human beings, and hope for eternal peace," the message said.

The ceremony has been held annually since 1994 when the cenotaph was established by Masashi Tsuno, a man arrested in the Philippines on suspicion of war crimes at the end of hostilities, but who was later acquitted.

Tsuno's supporters believe that the punishments meted out by the Tokyo Tribunals in the years after the war represented little more than victors' justice perpetrated in revenge.

- Thorn in regional relations -

Organiser Kazuaki Naka, 75, said the service has been held "to console the souls of war dead, who sacrificed their lives for their home country, whether their executions were fair or unfair."

Buddhism holds that descendents and those who outlive friends, colleagues or neighbours have a duty to care for the spirits of the dead.

The religion is practised alongside native Shintoism in Japan, an animistic belief system that also places obligations on the living to seek the repose of dead souls.

Abe's message to the ceremony could prove another thorn in the side of relations with China and South Korea, both of which have been angered by his visit to Yasukuni last December and his equivocation on Japan's wartime wrongdoing.

Top government spokesman Yoshihide Suga on Wednesday declined to comment on Abe's message, insisting it had been sent in his capacity as "a private person (and) president of the Liberal Democratic Party, and not as the Prime Minister".

He added that Japan had accepted the findings of the Tokyo Tribunals when it signed the Treaty of San Francisco in 1951.

A small but vocal right-wing tranche of Japanese society, most notably including the prime minister, continue to believe that Japan has been unfairly castigated for what they say was largely a just war, in which wrongdoing was perpetrated by individuals -- not states -- from all sides.

Beijing reacted angrily to the news, with a statement from foreign ministry spokesman Hong Lei castigating Abe for his "incorrect attitude" to the past.

"Facing history, reflecting profoundly on past militarist aggression, and making a clean break with militarism are an important foundation for rebuilding and developing Japan's relationship with its Asian neighbours," he said.

"We again urge the Japanese government to fulfil its commitment to reflecting on aggression, and to take concrete actions to win the trust of the people of its Asian neighbours and the international community."