Tokyo: On the 78th anniversary of the US dropping an atomic bomb on Hiroshima, Japan commemorated the event on Sunday. Hiroshima's mayor called for the elimination of nuclear weapons and dubbed the idea of nuclear deterrence put forth by the Group of Seven leaders as "folly." On the same day that the world remembers those who perished in the first nuclear attack, Russia has threatened to use nuclear weapons in its conflict with Ukraine. Additionally, the biopic "Oppenheimer," which details the development of the atomic bomb, has become a box office success in the US. The film has drawn criticism for largely omitting the use of nuclear weapons to destroy Hiroshima and Nagasaki, which were bombed three days later, on August 9, 1945. Also Read: The two NASA brothers Voyager 1 and 2 are now at the end of their lives The movie's debut in Japan hasn't yet been announced. The distributor of "Barbie," a popular movie released on the same day as "Oppenheimer," seized on "Barbenheimer" memes created by fans, which featured the actors in the title roles next to images of nuclear explosions, causing controversy in Japan as well. In May, the western city of Hiroshima, the seat of Prime Minister Fumio Kishida, attracted attention when he hosted a G7 summit there. In a statement, the G7 leaders reaffirmed their commitment to disarmament while stating that nuclear weapons should be used to deter aggression and avert war as long as they were in existence. Also Read: FAO and WHO to find Listeria sat together discussing tincture in US At 8:15 a.m. on Sunday (23:15 GMT on Saturday), when the bomb was detonated, a peace bell rang. A moment of silence was observed by about 50,000 attendees, including elderly survivors, as the summer heat reached 30 degrees Celsius (86 degrees Fahrenheit). At the ceremony, which Kishida also attended, Hiroshima Mayor Kazumi Matsui said that leaders from around the world "must face the reality that nuclear threats now being voiced by certain policymakers reveal the absurdity of nuclear deterrence theory." The prime minister claimed that, in part because of Russian nuclear threats, the path to a world free of nuclear weapons was becoming more difficult, but that this only underscored how crucial it was to rekindle global momentum in that direction. Antonio Guterres, the secretary-general of the United Nations, offered his support. Also Read: UN to drew the food price rates as got affected by the weather in the Sea His remarks were read aloud by a UN representative. "World leaders have visited this city, seen its monuments, spoken with its brave survivors, and emerged emboldened to take up the cause of nuclear disarmament," he said. "More should do so, as nuclear war drums are once more beating." The "Little Boy" bomb that was dropped on Hiroshima on August 6 killed thousands immediately and approximately 140,000 people by the end of the year. Japan gave up on August 15