Hiroshima on Saturday remembered the atomic bombing 77 years ago as officials, including the head of the United Nations, warned against nuclear weapons buildup as fears grow for another such attack amid Russia's war on Ukraine.

“Nuclear weapons are nonsense. They guarantee no safety, only death and destruction,” said UN Secretary General Antonio Guterres, who joined the prayer at the Hiroshima Peace Park. “Three quarters of a century later, we must ask what we've learned from the mushroom cloud that swelled above this city in 1945,” he said.