The Group of Seven leaders pledged Friday to boost sanctions on Russia to further undermine the country's "capacity to wage its illegal aggression" against Ukraine, hours after President Volodymyr Zelenskyy was reported to be set to attend the G-7 summit in person.

The latest commitment in a G-7 statement released in Hiroshima, a western Japanese city devastated by a U.S. atomic bomb on Aug. 6, 1945, came as concerns linger that Russia may use a nuclear weapon in its war in Ukraine launched 15 months ago.

The G-7 leaders, who began a three-day summit the same day, agreed that their nations will join hands to clamp down on schemes that allow Russia to circumvent the punitive measures through third-party countries, according to the statement.

Leaders of the Group of Seven industrialized economies attend the first day of their three-day summit on May 19, 2023, in the western Japan city of Hiroshima. Pictured clockwise from front right are Japanese Prime Minister Fumio Kishida, U.S. President Joe Biden, German Chancellor Olaf Scholz, British Prime Minister Rishi Sunak, European Commission President Ursula von der Leyen, European Council President Charles Michel, Italian Prime Minister Giorgia Meloni, Canadian Prime Minister Justin Trudeau and French President Emmanuel Macron. (Pool photo) (Kyodo) ==Kyodo

The leaders also said the G-7 states will urge Russia to "immediately" and "unconditionally" withdraw its troops from its neighbor, promising to "make every effort" to bring a "lasting peace in Ukraine as soon as possible."

The summit kicked off with a historic joint visit to a museum dedicated to documenting the world's first nuclear attack.

Zelenskyy will visit Hiroshima to participate in the summit, Japanese and U.S. government sources said Friday, in a surprise move that could prompt the G-7 leaders to unite further to support the Eastern European nation.

Japanese Prime Minister Fumio Kishida invited Zelenskyy to the G-7 summit during his trip on March 21 to Ukraine. If realized, Zelenskyy's visit to Japan would be the first since Russia invaded Ukraine in February 2022.

At the summit, the G-7 countries also agreed to uphold and strengthen the free and open international order based on the rule of law against the backdrop of China's increasing military assertiveness in the Asia-Pacific region.

As this year's G-7 chair, Kishida, who represents a Hiroshima constituency, has said he will be presenting his vision of a world without nuclear weapons.

On Friday morning, Kishida welcomed the G-7 leaders at the Peace Memorial Park, where the museum is located. It marked the first time for G-7 heads to visit there together, including those from the group's nuclear powers -- the United States, Britain and France.

Through the events at the park, the G-7 "affirmed its commitment toward realizing a world free of nuclear weapons" and reconfirmed its stance that any threat or use of nuclear weapons by Russia is "unacceptable," Japan's Foreign Ministry said in a press release.

Japan is hosting the G-7 summit, which also involves Canada, Germany, Italy plus the European Union, for the first time in seven years, following the one it held in the Ise-Shima area of the central prefecture of Mie.

The Group of Seven leaders take part in a photo session after offering wreathes at the cenotaph for atomic bomb victims at the Peace Memorial Park in Hiroshima on May 19, 2023, the first day of their three-day summit in the western Japan city. Pictured from left are European Council President Charles Michel, Italian Prime Minister Giorgia Meloni, Canadian Prime Minister Justin Trudeau, French President Emmanuel Macron, Japanese Prime Minister Fumio Kishida, U.S. President Joe Biden, German Chancellor Olaf Scholz, British Prime Minister Rishi Sunak and European Commission President Ursula von der Leyen. (Pool photo) (Kyodo) ==Kyodo

At the outset of the meeting in Hiroshima, Kishida said the G-7 needs to join hands to avoid "division and confrontation" and achieve a "cooperative international community," vowing to strive to bolster engagement with partners sharing the same values.

The agenda for the first day included the global economy, digital technology, the security situation in the Indo-Pacific region and nuclear disarmament.

With China not ruling out the possibility of using its military might to reunify self-ruled democratic Taiwan with the mainland, the G-7 states emphasized opposition to any unilateral attempt to change the status quo by force or coercion.

The G-7 heads, meanwhile, confirmed the importance of dialogue with China to prevent any emergency in nearby waters, Kishida told reporters later Friday, with Sino-U.S. tensions escalating recently.

The G-7 members shared the view that stability in the Taiwan Strait is essential for regional peace, he said.

Kishida also said the G-7 leaders reached an agreement on how to advance nuclear disarmament and non-proliferation, stressing that they mapped out an outcome document on the issue.

Japanese Prime Minister Fumio Kishida (C) and other participants of the Group of Seven summit pose for a photo during talks over dinner at a traditional Japanese inn in Hatsukaichi in Hiroshima Prefecture on May 19, 2023, on the first day of the three-day event in the western Japanese city of Hiroshima. (Kyodo) ==Kyodo

The G-7 will call on nuclear nations to disclose their capabilities to ensure transparency and continue trying to reduce the number of weapons, while positioning the Nuclear Non-Proliferation Treaty as the foundation for disarmament, Kishida said.

The NPT came into effect in 1970. The treaty designates five nations -- Britain, China, France, Russia and the United States -- as authorized possessors of nuclear arsenals, prohibiting other countries from acquiring them.

As for the world economy, the G-7 affirmed the significance of building reliable supply chains, with alarm rising about China's tighter grip on critical components that has jeopardized the national security of other major powers.

Among other key topics at the G-7 summit were risks associated with generative artificial intelligence, which can utilize vast amounts of data from the internet and other sources to generate text, images, or other media in a human-like way.

The G-7 leaders agreed that their countries will formulate the group's policy on generative AI by the end of this year. Responses to the fast-developing technology, featuring applications such as AI chatbot ChatGPT, have varied among member nations.

Hiroshima Mayor Kazumi Matsui (5th from L) speaks to leaders of the Group of Seven industrialized economies during their visit to the Peace Memorial Park in Hiroshima on May 19, 2023, on the first day of the three-day G-7 summit in the western Japan city. (Pool photo) (Kyodo) ==Kyodo

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