Japan's Nagasaki on Sunday commemorated the 81st anniversary of the US atomic bombing of the city in the closing days of World War II. During the ceremony, Prime Minister Sanae Takaichi made ambiguous remarks on Japan's non-nuclear principles, while Nagasaki Mayor Shiro Suzuki condemned nuclear weapons as an "absolute evil."

A moment of silence was observed at 11:02 a.m. local time, the exact moment when a plutonium atomic bomb dropped by a US bomber exploded over Nagasaki on August 9, 1945.

The attack on the southwestern Japanese city came three days after the atomic bombing of Hiroshima in western Japan, and is believed to have killed around 74,000 people in Nagasaki by the end of 1945, while leaving many others suffering from long-term health effects.

The mayor of Nagasaki delivered a declaration at the annual memorial ceremony, calling nuclear weapons an "absolute evil" and urging the Japanese government to fulfill its historical responsibility.

He called on the Japanese government to "uphold the ethos of peace enshrined in the Japanese constitution, which embodies a determination to forever renounce war, as well as the country's Three Non-Nuclear Principles."

Takaichi reiterated her ambiguous remarks made at the Hiroshima memorial ceremony days earlier. She said that Japan "is upholding" the Three Non-Nuclear Principles, without explicitly pledging that the country would continue to uphold them, marking a subtle departure from the wording used by previous prime ministers.

Japan's opposition lawmakers had previously criticized Takaichi's remarks as merely an explanation of the current situation, saying they lacked a clear commitment to maintaining the non-nuclear principles in the future.

On the same day, Russian Ambassador to Japan Nikolay Nozdrev warned of the consequences of Japan abandoning its non-nuclear status in an interview with RIA Novosti.

He said that abandoning the non-nuclear principles would violate Japan's long-standing commitments as a non-nuclear state. He also warned that any Japanese move to drop its non-nuclear status would breach the Nuclear Non-Proliferation Treaty and trigger countermeasures from countries in the region.

Japan's Three Non-Nuclear Principles, which prohibit possessing, producing, or allowing the introduction of nuclear weapons into Japanese territory, were formally adopted by the Japanese parliament in 1971 and have since become the cornerstone of the country's nuclear policy.

Japanese media previously reported that the Takaichi administration was considering revising the principle of not allowing the introduction of nuclear weapons into Japan as part of planned revisions to the country's three key security documents later this year.

In July, Defense Minister Shinjiro Koizumi publicly said during an online program that Japan should discuss nuclear-related policies without taboo. These developments have fueled continued concern across Japanese society.

(With input from Xinhua)