TOKYO » Japan’s conservative prime minister, Shinzo Abe, sent a message of support earlier this year to a ceremony honoring more than 1,000 Japanese who died after being convicted as war criminals following World War II, a government spokesman said Wednesday. The move could worsen frictions between Japan and its neighbors, particularly China, over bitter memories of World War II in the region.

Abe wrote in the message, sent to the ceremony held on April 29 at the Koyasan temple in western Japan, that the convicted war criminals had "sacrificed their souls to become the foundation of the fatherland," according to a news report that first appeared in the Asahi Shimbun, a major Japanese newspaper.

The spokesman, Chief Cabinet Secretary Yoshihide Suga, confirmed the report, saying that Abe had sent the message not in his public capacity as prime minister but as a private citizen, signing his name as the head of the governing Liberal Democratic Party. The report said the message was read aloud at the ceremony, which Abe did not attend.

The ceremony, which is held annually but is not well known in Japan, honors 1,180 Japanese who were executed or died in prison after being convicted of war crimes by Allied tribunals. The tribunals convicted the Japanese soldiers for crimes such as the massacre and rape of civilians and the killing of Allied prisoners of war.

The ceremony’s organizers share a view held by many on Japan’s right that the tribunals wrongfully convicted the men in rulings that amounted to nothing more than victor’s justice.

On Wednesday, Suga tried to distance his government from those views, saying that Japan accepted the Allied judgments when it signed the San Francisco Peace Treaty in 1952 to officially end the war.

While Abe’s message to the ceremony appeared carefully worded, he has in the past openly questioned whether Japan was actually the aggressor during the war. In a parliamentary budget committee hearing last year, he said only Japanese were condemned of war crimes in the Pacific war because the victorious Allies were able to impose their view of the war.

Such sentiments have made him the target of criticism by China, a victim of Japan’s wartime empire-building that has accused Abe of trying to exonerate Japanese militarism.

China’s Ministry of Foreign Affairs released a statement criticizing Abe’s support of the war criminals ceremony.

"We urge the Japanese side to truly abide by its statements and promises to reflect on its aggression" in wartime, a spokesman said on the ministry’s website.

© 2014 The New York Times Company