NAGASAKI - Nagasaki on Sunday warned nuclear powers and deterrence-reliant nations 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.

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