NAGASAKI - Nagasaki on Sunday warned nuclear powers and nations relying on nuclear deterrence of the increased risk of a war using nuclear weapons, as the Japanese city marked the 81st anniversary of the U.S. atomic bombing with a resolve to prevent such a tragedy from ever happening again.

"Nuclear weapons are not a 'necessary evil' but an 'absolute evil,' and can never coexist with humanity," Mayor Shiro Suzuki said in the Peace Declaration read during the annual memorial ceremony for the attack on the southwestern city, which followed the atomic bombing of Hiroshima three days earlier.

Adding cadence and vocal inflection, Suzuki's powerful voice pierced through the Peace Park as he called the concept of nuclear deterrence "extremely dangerous and fragile."

This year's commemoration comes amid geopolitical tensions in the wake of the Middle East conflict and Russia's invasion of Ukraine.

A moment of silence was held at 11:02 a.m., when the plutonium device codenamed "Fat Man" was dropped by a U.S. bomber and exploded over Nagasaki. It remains the last place to have suffered a nuclear attack.

Still, more than 12,000 nuclear warheads exist, Suzuki pointed out. He expressed concern over unpredictability in the conflicts in Ukraine and the Middle East, where nuclear states are involved, referring to Russia's invasion of Ukraine and the U.S.-led war on Iran.

Prime Minister Sanae Takaichi delivered a speech following a brief heckle from the crowd, reiterating what she said in the Hiroshima commemoration last Thursday that Japan "is upholding" the three nonnuclear principles.

She said that under a pledge to ensure Nagasaki remains the last place to suffer a nuclear attack and with a mission as the only country to have experienced the horror of nuclear devastation in war, Japan will promote "realistic and practical" efforts toward realizing a world free of such weapons.

"The importance of promoting an accurate understanding around the world of the realities of the atomic bombings is growing ever greater," she added.

In his speech, the Nagasaki mayor noted the failure to adopt a final document at the review conference of the Nuclear Non-Proliferation Treaty in May, saying trends such as the modernization and enhancement of nuclear weapons only "further fuel a vicious cycle of even greater mutual distrust, confrontation and division."

The review conference, held every five years in principle, ended for the third consecutive time without reaching consensus after a monthlong meeting in New York.

Citing a reversal of the decades-long trend toward reductions in nuclear arsenals and increasing nuclear saber-rattling, U.N. Secretary General Antonio Guterres warned, "Year by year, the risk of miscalculation, escalation, and conflict keeps going up," calling the situation "unacceptable" and saying that "humanity should not have to live under permanent threat."

In the statement read out on his behalf, Guterres stressed the need to recognize that security around the world is "interdependent" and that "nuclear weapons only fuel uncertainty."

As debate grows over whether to rethink Japan's longstanding three nonnuclear principles of not producing, possessing or allowing nuclear weapons, Takaichi met atomic bomb survivors after Thursday's Hiroshima ceremony, saying only that the government "is upholding" the policy.

Suzuki, in his address, also urged the 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."

Furthermore, as in Hiroshima's Peace Declaration, he called on the government to attend a review conference of the Treaty on the Prohibition of Nuclear Weapons later this year. The conference, aimed at advancing the treaty's goal of banning the development, production, use and possession of nuclear weapons, is to be convened in November.

In the early morning, amid the cool humidity, many people gathered at the park and other significant sites related to the bombing to offer their prayers before the ceremony began.

"I come here every year," said Toyomi Okada, an 87-year-old atomic bomb survivor, known as hibakusha.

Okada was 6 years old when the bomb exploded near her home, about 4.2 kilometers from the hypocenter. Although she does not remember the details of that day, she remembers the devastation that remained in its aftermath.

"I was able to see this park all the way from my house," she said, recalling how the explosion had blown away all the buildings between her home and the park.

Okada still lives in her childhood home.

The nuclear attack on Nagasaki on Aug. 9, 1945 is believed to have killed around 74,000 people in the city by the end of the year and left many others suffering from its effects.

Japan surrendered on Aug. 15 of the same year, bringing an end to World War II.

Atomic bomb survivors and their supporters are racing against time to pass on memories of the tragedy, with the average age of officially recognized survivors of the two atomic bombings exceeding 86.

"We are now in a critical moment where we can still listen directly to the voices of the hibakusha. Therefore, we are determined to hand down the memories of the atomic bombings and the thoughts of the hibakusha to future generations," Suzuki said.

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