m., the moment in 1945 that a US plane dropped the first atomic bomb deployed in war.

An estimated 140,000 people had died there by the end of that year.

It was followed by a second atomic bombing three days later on Nagasaki, the last city to be subjected to nuclear warfare. About 70,000 people died soon after the blast there, and Japan surrendered on Aug 15, 1945.

Decades after the bombings, thousands of people still continue to die every year from the effects of radiation from the blasts, such as leukaemia and other types of cancers.

Nagasaki plans its own memorial ceremony Sunday.

After Hiroshima's commemorative event, Aso signed a settlement of a six-year-long legal battle between the government and 306 people who had sought to be recognised as suffering from ailments related to the 1945 bombings.

Such recognition allows the patients to receive government aid to cover their medical treatment. The settlement signed Thursday guarantees compensation for the plaintiffs.