- US president and Japanese PM lay wreath at Hiroshima memorial
- Obama says memory of Hiroshima bombing "must never fade"
- His speech is watched by survivors of atomic blast
Barack Obama has become the first US incumbent president to visit Hiroshima, the Japanese city where America dropped an atomic bomb in 1945.
Accompanied by Shinzo Abe, the Japanese prime minister, Obama laid a wreath at the Hiroshima Peace Memorial Park on Friday before paying tribute to the 140,000 victims of the world's first nuclear attack.
"Seventy-one years ago, death fell from the sky and the world was changed," Obama said in a speech.
He told the assembled crowd that the world has a shared responsibility to ask how to prevent the suffering that took place in Hiroshima on August 6, 1945, the day the US dropped the atomic bomb on the western Japanese city.
The bomb "demonstrated that mankind possessed the means to destroy itself".
|Obama lays a wreath at a cenotaph in Hiroshima Peace Memorial Park [Toru Hanai/Reuters]
He said: "Why did we come to this place, to Hiroshima? We come to ponder a terrible force unleashed in the not-so-distant past. We come to mourn the dead.
"Their souls speak to us, they ask us to look inward, take stock of who we are."
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Obama also greeted ageing survivors and embraced one elderly man who appeared overcome with emotion.
Al Jazeera's Harry Fawcett, reporting from Hiroshima, said Obama tried in his speech to strike the right balance in terms of the audience in Japan but also people listening to him back in the US.
"This is something that no president in the 71 years since the bomb was dropped here has felt able to do," our correspondent said.
"So he tried to strike that balance by both talking about the specifics of what happened here, but also trying to put in the context not only of the Second World War, but also of human morality."
Source: Al Jazeera and agencies