HIROSHIMA — Japan marked 64 years yesterday since the city of Hiroshima was hit in the world’s first atomic bomb attack with a call for a nuclear-weapons-free world, a goal backed by U.S. President Barack Obama.

The mayor of Hiroshima, the city where 140 000 people died from the blast, renewed his call for the abolition of what he said are 24 000 remaining nuclear warheads over the next decade as he led the solemn ceremony.

About 50 000 people, including “hibakusha” or atom bomb survivors, politicians and envoys from 59 countries and the United Nations, gathered near the A-bomb Dome, the skeleton of a hall burnt by the bomb’s intense heat.

“The abolition of nuclear weapons is the will not only of the hibakusha, but also of the vast majority of people on this planet,” said the mayor, Tadatoshi Akiba, head of the international group Mayors for Peace.

Akiba praised Obama for stating at a speech in Prague this year that the U.S., as the only country to have ever used an atomic weapon, has “a moral responsibility” to work toward their eventual abolition.

“Together, we can abolish nuclear weapons,” Akiba said. “Yes, we can.”

Those at the memorial ceremony said silent prayers at 8.15 am, the exact moment the bomb was dropped in 1945.

Three days after the attack, the U.S. dropped a second atomic bomb on Nagasaki, which killed 70 000 people.

Japan surrendered on August 15, ending World War 2 in the Pacific.

Japan’s Prime Minister Taro Aso pledged at the ceremony that Japan will lead the international community in abolishing nuclear weapons.

However, debate continues over the merit of the atom bombings with some saying the attacks brought a quick end to the war and others saying they were an unnecessary atrocity.