Kerry 'deeply moved' by visit to Hiroshima memorial

John Kerry yesterday said he was "deeply moved" by his unprecedented visit to the Hiroshima atomic bomb memorial -- and urged President Barack Obama also to make the trip.

The US secretary of state, who was joined by other G7 foreign ministers, is the highest-ranking administration official to pay respects at the spot where American planes launched the first-ever nuclear attack more than seven decades ago.

Washington officials say Obama is considering a trip to Hiroshima late next month around the time of a Group of Seven summit, which is being held in another part of Japan.

An Obama visit would have huge symbolic importance as the first to Hiroshima by a sitting US president.

"I want to express on a personal level how deeply moved I am" to be the first US secretary of state to visit Hiroshima, Kerry told reporters yesterday as he and his G7 counterparts wrapped up two days of talks.

A museum at the memorial site is a "gut-wrenching display that tugs at all your sensibilities as a human being", Kerry said.

About 140,000 people died from the Hiroshima blast on August 6, 1945, or later from severe radiation exposure. The city, a key military installation during the war, was flattened by the massive detonation.

The atomic bombing of Nagasaki followed three days later, killing some 74,000 people. Japan surrendered within a week to end World War II.

"Everyone should visit Hiroshima, and everyone means everyone," Kerry said. "I hope one day the president of the United States will be among the everyone who is able to come here."

Children hold up flags from the G7 countries in the wind as the foreign ministers visit the Peace Memorial Park in Hiroshima. Photo: AFP

But Kerry declined to comment on the likelihood of an Obama visit. "Whether or not he can come as president, I don't know," he said.

After a G7 meeting in Hiroshima yesterday, Kerry said the United States is prepared to "ratchet up" pressure on North Korea after its latest provocations but remains open to talks.

"It is still possible we will ratchet up (the pressure) even more depending on the actions of the DPRK (North Korea)," he told reporters.

"But we have made it clear... we are prepared to negotiate a peace treaty" on the Korean peninsula, he said, repeating that such a move would depend on North Korea's denuclearisation.

Kerry had said in February that a denuclearised North Korea could one day enter talks with Washington on a treaty formally ending the Korean War of 1950-53.

The conflict ended with an armistice and not a peace treaty. The US insists that Pyongyang must denuclearise as a condition for talks on a peace pact.