Japanese Prime Minister Fumio Kishida and U.S. Ambassador to Japan Rahm Emanuel on Saturday pledged their countries' unity against the use of nuclear weapons as they visited the Hiroshima atomic bomb memorial amid growing fears over Russia possibly using the devastating arms.

Emanuel, once a top aide to former President Barack Obama, and Kishida, a lawmaker representing a constituency in the city, offered flowers for the victims of the 1945 U.S. atomic bombing at the Peace Memorial Park near ground zero. It followed their visit to the Peace Memorial Museum, which has belongings of the victims, photos and other materials on display.

Japanese Prime Minister Fumio Kishida (2nd from L) and U.S. Ambassador to Japan Rahm Emanuel (3rd from R) visit Hiroshima's Peace Memorial Park on March 26, 2022. (Kyodo) ==Kyodo

"I have confirmed cooperation with President Biden with regard to seeking a world without nuclear weapons, and I shared such a thought with Ambassador Emanuel, too," Kishida told reporters after holding talks with the ambassador in the city, noting the U.S. envoy's Hiroshima visit will send out a strong message to the international community.

But "the Ukraine crisis has once again shown us the difficult path toward realizing a world without nuclear weapons," the premier said.

He suggested an intent to add more sanctions on Russia and support Ukraine and neighboring countries together with others including the Group of Seven industrialized nations.

Japanese Prime Minister Fumio Kishida (R) and U.S. Ambassador to Japan Rahm Emanuel offered flowers at Hiroshima's Peace Memorial Park on March 26, 2022. (Kyodo)

Emanuel said in a statement released after the visit that "we live in unprecedented times as Russia threatens the use of nuclear weapons, something that was once unthinkable, even unspeakable."

"The history of Hiroshima teaches us that it is unconscionable for any nation to make such a threat," he said.

Their visit to one of the two atomic-bombed cities in Japan comes as Russian President Vladimir Putin recently hinted at using nuclear weapons in the face of Ukraine's resistance and severe economic sanctions imposed by Western nations following its invasion of Ukraine on Feb. 24.

Japan has joined the United States and European countries in imposing sanctions on Russia, including freezing its central bank's assets, disconnecting its key financial institutions from a major international payment system and imposing export bans and controls. It has said it is preparing additional measures as the war in Ukraine drags on.

"It is a big step forward that the U.S. ambassador visited Hiroshima at a time when there is concern that Russia might use nuclear weapons," said Toshiko Tanaka, 83, who has been speaking about her atomic bomb experience in Japan and abroad.

Emanuel said he is hoping to visit the other atomic-bombed city, telling reporters his journey will not end until he visits Nagasaki.

Earlier in the day, he tweeted that he met with Shigeaki Mori, an atomic bomb survivor who in 2016 hugged Obama during his historic visit to the city, the first by a sitting U.S. president. Kishida, a foreign minister at the time, played an active role in realizing the visit.

Emanuel and Kishida were initially scheduled to visit the city on Feb. 26 but postponed it following the Russian invasion of Ukraine.

The ambassador expressed his desire to visit the western Japanese city when he first met Kishida in February as the envoy to Japan.

In January, the Japanese and U.S. governments issued a joint statement in which they urged world leaders to visit Hiroshima and Nagasaki to raise and sustain awareness.

"I hope the ambassador will tell President Biden that he should visit Hiroshima and see what really happened here," 80-year-old Toshiyuki Mimaki, the head of a major atomic bomb survivors' group in Hiroshima, said after watching Kishida and Emanuel laying flowers at the memorial park.

Emanuel said President Joe Biden would be eager to visit at least either of the cities as the envoy did.

More than 50 countries and regions have ratified the Treaty on the Prohibition of Nuclear Weapons, the first international pact outlawing the development, testing, possession and use of nuclear weapons that came into effect in January last year.

But nuclear-weapon states, such as the United States, are not part of the treaty. Japan has not signed the pact due to its security alliance with the United States, which offers the shelter of its nuclear umbrella.

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