In the run-up to the summit, participants had expected Zelenskyy to appear at least virtually. But until Friday there had been no confirmation that he would make the potentially dangerous trip from Kyiv, the furthest he will have traveled from his country since last year's invasion.

"He was always going to participate in the G-7 in some form or fashion," said John Kirby, a spokesman for the White House's National Security Council, who would not confirm that the Ukrainian leader would appear in person. "It's really important right now, at this inflection point in the war in Ukraine, that G-7 leaders hear directly from him about conditions on the ground and what he needs going forward."

A charismatic presence in his trademark green fatigues, Zelenskyy will presumably make the case that his nation’s survival hinges on a continued flow of money and sophisticated weaponry from the U.S. and its allies.

Before heading to Japan, Zelenskyy was in Saudi Arabia for Friday's Arab League summit, seeking closer ties with countries beyond the West. He will then head to a G-7 summit meeting that has already agreed on new steps to make the war even costlier for Russia.

Biden attended a working luncheon Friday focused on the conflict — papers spread across a round table with flags of each country in the background. Present were the leaders of Japan, Germany, France, Italy, Canada, the United Kingdom, the European Commission and the European Council.

A subsequent joint statement released by the G-7 leaders laid out a series of new sanctions. Looking to undercut the Kremlin's war-making capacity, the nations agreed to restrict exports to Russia that include industrial machinery, tools and technology.

“We will starve Russia of G-7 technology, industrial equipment and services that support its war machine,” the statement reads.

“Our commitment to continue tightening the screws on Russia remains as strong as it was last year,” a Biden administration official said ahead of the summit, speaking on condition of anonymity because they were not authorized to speak on the record.

But recent polling shows that Americans are tiring of the war and are eager to see an end date.

Russia failed to swiftly conquer its smaller neighbor but has given no sign that it is prepared to withdraw forces. Nor is Kyiv about to surrender. Ukraine is readying a counteroffensive to retake occupied land and showcase the difference Western support can make on the battlefield.

Biden, who last saw Zelenskyy in person during a surprise trip to Kyiv three months ago, vowed at the time that the U.S. would stand with Ukraine for “as long as it takes.”

That open-ended commitment will test the resolve and patience of Americans in an election season, as the Biden administration spends billions to help keep Ukraine in the fight.

The war figures to be an issue in the 2024 presidential race. Republican front-runner Donald Trump has stopped short of saying he wants Ukraine to win and told a recent CNN town hall that, if elected, he’d end the conflict in 24 hours by meeting with Zelenskyy and Russian President Vladimir Putin.

An unexpected domestic problem has intruded on Biden's trip: The debt ceiling fight back in Washington.

Biden had originally planned to visit Papua New Guinea and Australia as part of an effort to rally U.S allies and curb China's growing influence in the Pacific. He canceled those legs of the trip so that he could return to the White House on Sunday and resume talks over raising the debt ceiling and averting an unprecedented default that could have global implications.

Biden left a group dinner a little early on Friday to get an update from his negotiating team, the White House said.

"It's a minor miracle that Biden went ahead with the trip to Hiroshima," said Daniel Russel, former director of Asian affairs in the Obama White House. "I'm glad he did and we should all pray that this [debt ceiling fight] gets wrapped up, because the consequences would be devastating -- and not only for the U.S. Everyone is concerned."

Beyond sanctions, Zelenskyy has asked for advanced F-16 fighter jets to help repel Russian forces. So far, the Biden administration has declined to provide the planes out of concern that weapons capable of reaching Russian soil would risk escalating the war. But the U.S. has invited Ukrainian pilots to train on simulators to assess how long it would take them to learn to fly the aircraft.

At the summit, Zelenskyy will have a fresh opportunity to push for the jets.

“It’s very helpful," Russel said of Zelenskyy's visit. "If the industrialized countries get Ukraine fatigue before Russia gets war fatigue and tired of fighting, then there’s going to be a big problem. Zelenskyy has been brilliant in ensuring that the world sees the situation for what it is, and that it doesn’t burn out and get tired.”

The summit's location is symbolic of the mortal threat that is an everyday concern for Ukraine as well as Asian countries living in the shadow of nuclear-armed China and North Korea.

During World War II, the U.S. leveled Hiroshima with a single atomic bomb. On Friday morning, Biden and his counterparts toured the Hiroshima Peace Memorial Museum and met a woman who survived the attack.

In the park outside, the leaders laid wreaths and planted a tree overlooking the skeletal remains of a once-domed building that Japan has preserved as a reminder of the bomb's toll.