Ukrainian President Volodymyr Zelenskyy huddled with some of his biggest backers in Hiroshima on Sunday, building momentum for his country's war effort even as Russia claimed a symbolic victory on the battlefield.

The Ukrainian leader's in-person appearance in his trademark olive drab during the final day of the Group of Seven summit underscored the centrality of the war for the bloc of rich democracies. It also stole much of the limelight from other priorities, including security challenges in Asia and outreach to the developing world, that the leaders focused on at the three-day gathering.

Zelenskyy held two major rounds of meetings Sunday, one with G7 leaders and a second with them and a host of invited guests including India, South Korea and Brazil. He also held one-on-one talks with several of the leaders.

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U.S. President Joe Biden announced a new military aid package worth $375 million for Ukraine during his meeting with Zelenskyy, saying the U.S. would provide ammunition and armored vehicles. That fresh pledge came days after the U.S. agreed to allow training on American-made F-16 fighter jets, laying the groundwork for their eventual transfer to Ukraine.

"We have Ukraine's back and we're not going anywhere," Biden said.

Zelenskyy thanked Biden for the support, adding that "we will never forget."

Even before Zelenskyy landed Saturday aboard a French plane, the G7 nations had unveiled a slew of new sanctions and other measures meant to punish Moscow over its invasion that began in February last year.

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Hanging over Sunday's talks was the claim by Russia's Defense Ministry that forces of the Wagner private army, backed by Russian troops, had seized the Ukrainian city of Bakhmut. The eight-month battle for the eastern city — seen by both sides as a major symbolic prize — has been the longest and likely the bloodiest of the war.

Asked if Bakhmut was still in Ukraine's hands, Zelenskyy said he thought that Russian forces had finally taken the city in a siege that "destroyed everything."

"For today, Bakhmut is only in our hearts. There is nothing in this place," Zelenskyy said, adding that the fight had left nothing in Bakhmut but a lot of "dead Russians."

While Ukraine was the overwhelming focus of the summit, the leaders of Japan, the United States, the United Kingdom, France, Germany, Canada and Italy, as well as the European Union, also aimed to address global worries over climate change, AI, poverty, economic instability and nuclear proliferation.

Biden also aimed to reassure world leaders that the U.S. would not default because of the debt limit standoff that has cast a large shadow over his trip.

Two U.S. allies — South Korea and Japan — continued efforts Sunday to improve ties that have often been hurt by lingering anger over issues linked to Japan's brutal 1910-1945 colonization of the Korean Peninsula. Japanese Prime Minister Fumio Kishida and South Korean President Yoon Suk Yeol visited a memorial to Korean victims, many of them slave laborers, of the Aug. 6, 1945, atomic bombing.

Washington wants the two neighbors, both of which are liberal democracies and bulwarks of U.S. power in the region, to stand together on issues, including rising aggression from China, North Korea and Russia.

Biden, Yoon and Kishida met briefly as a group outside the summit venue posing for photos in front of Hiroshima Bay. Biden invited the two leaders to visit Washington for a trilateral meeting and they accepted, a US official who briefed reporters on condition of anonymity said.

Zelenskyy also met on the sidelines of the summit with Indian Prime Minister Narendra Modi, their first face-to-face talks since the war, and briefed him on Ukraine's peace plan, which calls for the withdrawal of Russian troops from the country before any negotiations.

India, the world's largest democracy, has avoided outright condemnation of Russia's invasion. While India maintains close ties with the U.S. and its Western allies, it is also a major buyer of Russian arms and oil.

Summits like the G7 are a chance for leaders to put pressure on one another to align or redouble their diplomatic efforts, according to Matthew Goodman, an economics expert at the Center for Strategic and International Studies think tank in Washington.

"Zelenskyy's presence puts some pressure on G7 leaders to deliver more — or explain to him directly why they can't," he said.

Russian Foreign Minister Sergey Lavrov criticized the summit for aiming to isolate both China and Russia.

"The task has been set loudly and openly: to defeat Russia on the battlefield, but not to stop there, but to eliminate it as a geopolitical competitor," he said.

The G7, however, has vowed to intensify the pressure, calling Russia's assault on Ukraine "a threat to the whole world in breach of fundamental norms, rules and principles of the international community."

The group took a different approach in its comments on China, the world's No. 2 economy. There is increasing anxiety that Beijing, which has been steadily building up its nuclear weapons program, could try to seize self-governing Taiwan by force, sparking a wider conflict.

The G7 said they did not want to harm China and was seeking "constructive and stable relations" with Beijing, "recognizing the importance of engaging candidly with and expressing our concerns directly to China."

They also urged China to pressure Russia to end the war in Ukraine and "support a comprehensive, just and lasting peace."

China's Foreign Ministry said that "gone are the days when a handful of Western countries can just willfully meddle in other countries' internal affairs and manipulate global affairs. We urge G7 members to ... focus on addressing the various issues they have at home, stop ganging up to form exclusive blocs, stop containing and bludgeoning other countries."

The G7 also warned North Korea, which has been testing missiles at a torrid pace, to completely abandon its nuclear weapon ambitions, "including any further nuclear tests or launches that use ballistic missile technology," the leaders' statement said.

The G7 leaders have rolled out a new wave of global sanctions on Russia, now the most-sanctioned country in the world, as well as plans to enhance the effectiveness of existing financial penalties meant to constrain President Vladimir Putin's war effort.

The latest sanctions aimed at Russia include tighter restrictions on already-sanctioned people and firms involved in the war effort. More than 125 individuals and organizations across 20 countries have been hit with U.S. sanctions.

Russia had participated in some summits with the other seven countries before being removed from the then-Group of Eight after its 2014 annexation of Crimea.

Kishida, mindful of the host city's symbolic importance, has twice taken leaders to visit to a peace park dedicated to the tens of thousands who died in the world's first wartime atomic bomb detonation. He had wanted nuclear disarmament to be a major focus of discussions.

Some survivors of the 1945 atomic bomb attack and their families worried that Zelenskyy's inclusion at the summit overshadowed that priority. Etsuko Nakatani, an activist whose parents survived the Hiroshima atomic bombing, said the leader's visit was "not appropriate for Hiroshima, which is a peace-loving city."

Protesters carrying "No War No G7" banners briefly scuffled with riot police deployed as part of a massive show of force throughout the city during a march Sunday.

The G7 leaders also discussed efforts to strengthen the global economy and address rising prices that are squeezing families and government budgets around the world, particularly in developing countries in Africa, Asia and Latin America. They reiterated their aim to pull together up to $600 billion in financing for the G7's global infrastructure development initiative, which is meant to offer countries an alternative to China's investment dollars.