Japan marks 1945 Hiroshima atomic bomb

Tens of thousands bowed their heads at a ceremony in the Japanese city of Hiroshima on Wednesday, the 63rd anniversary of the world's first atomic attack, as the city's mayor hit out at countries that refuse to abandon their bombs.

A bell tolled at 8:15 a.m. to mark the exact moment when the bomb dubbed "Little Boy" was dropped on the city, killing tens of thousands immediately and many more later from radiation sickness.

"We who seek the abolition of nuclear weapons are the majority," mayor Tadatoshi Akiba said in a speech at the Peace Memorial Park, attended by the ambassador of nuclear-armed China, as well as Prime Minister Yasuo Fukuda and elderly survivors of the attack.

"Last year 170 countries voted in favour of Japan's U.N. resolution calling for the abolition of nuclear weapons. Only three countries, the United States among them, opposed this resolution," he said.

The United States and other world powers fear Iran is developing nuclear weapons, while Tehran says its atomic programme is for power generation. Washington and others have warned of more sanctions against Tehran, which they accuse of playing for time in the dispute.