NEW YORK — President Joe Biden on Tuesday forcefully touted his record of rebuilding alliances and defending democracy around the globe, as Israeli strikes in Lebanon and the growing threat of a regional war in the Middle East cast a pall over his final United Nations address.

Biden reflected on the arc of his five-decade political career and said he believed the world was at an “inflection point” given the myriad conflicts unspooling across the globe, including wars in Ukraine, Gaza and Sudan.

The president also cast his decision this summer not to seek a second term as one that continued his push to protect democracy, which he called one of the driving goals of his presidency. “My fellow leaders, let us never forget — some things are more important than staying in power,” Biden told the assembled heads of state. “It’s your people that matter the most. Never forget, we are here to serve the people, not the other way around.”

But looming over Biden’s speech — in which he touted his work defending Ukraine and combating climate change, among other things — was the quickly escalating violence between Israel and the Lebanese militant group Hezbollah.

Israeli strikes in Lebanon this week have killed more than 550 people, including 50 children, according to Lebanon’s Health Ministry, and Israeli officials have said they are turning to a new phase of the war focused on the country’s northern border with Lebanon rather than its southern border with Gaza.

“Full scale war is not in anyone’s interest. The situation has escalated,” Biden said. “A solution is still possible. In fact, it remains the only path to lasting security and to allow the residents of both countries to return to their homes.”

Hezbollah began firing rockets into Israel after the Oct. 7 attacks, forcing Israel to evacuate some 67,500 people from its northern communities, according to the Taub Center, and many of those towns remain empty. Israel’s retaliatory strikes on southern Lebanon have displaced more than 111,000 people, according to the United Nations.

Biden has focused most of his administration’s diplomatic efforts on trying to achieve a cease-fire between Israel and Hamas, based in Gaza, and he defended those efforts Tuesday. “Now is the time for the parties to finalize the terms,” Biden said. “Bring the hostages home, secure security for Israel and Gaza free of Hamas’s grip, ease the suffering in Gaza, and end this war.”

But senior U.S. officials acknowledge privately that a cease-fire in Gaza is increasingly elusive, saying that neither side appears to truly want a deal. Hezbollah has vowed to continue firing rockets into Israel as long as the war continues, and now Israeli officials have vowed to eliminate the threat on their northern border and have significantly escalated attacks in recent days.

At the United Nations, Biden recounted the Oct. 7 attack, when Hamas militants broke through the Israel-Gaza border fence and killed 1,200 people and took some 250 hostage. He also spoke of Palestinian suffering under Israel’s retaliatory military campaign, which has killed more than 41,000 Palestinians, according to the Gaza Health Ministry, as well as resulted in mass displacement and fueled an ongoing humanitarian catastrophe in the enclave.

“The world must not flinch from the horrors of Oct. 7. Any country — any country — would have the right and responsibility to ensure that such an attack can never happen again,” Biden said, noting that he has met and grieved with hostage families, who are “going through hell.”

He added: “Innocent civilians in Gaza are also going through hell. Thousands and thousands killed, including aid workers. Too many families dislocated, crowding into tents, facing a dire humanitarian situation. They didn’t ask for this war Hamas started.”

The first Arab leader to address the gathering, Jordan’s King Abdullah II, recounted the pain of witnessing the suffering of the conflict and warned that it could get worse as Israel steps up its bombardment of Lebanon.

“The Israeli government’s assault has resulted in one of the fastest death rates in recent conflicts, one of the fastest rates of starvation caused by war, the largest cohort of child amputees and unprecedented levels of destruction,” Abdullah said.

“The world is watching, and history will judge us by the courage we show,” he added. “And it is not just the future that will hold us accountable. So will the people of the here and now.”

While Abdullah was careful not to criticize the United States directly, his comments reflected the frustration among many U.S. allies, including Arab nations and those in the Global South, at Biden’s policy of providing largely unconditional military support to Israel, even as the death toll in Gaza has grown.

Israel has said it has little choice but to try to eradicate Hamas in Gaza and that the high death toll is a direct result of the militant group’s strategy of embedding among civilians. Still, many human rights and aid groups say Israel has done little to guard against civilian casualties and has actively obstructed aid.

Biden spent much of Monday’s speech, which was intended in large part to highlight his legacy as a global leader, focusing on his administration’s work defending Ukraine against Russia’s invasion, as he urged the United Nations to “stand firm against aggression.”

He said he and Vice President Kamala Harris, the Democratic presidential nominee, recognized Russia’s invasion as “an assault on everything this institution is supposed to stand for.” While describing his Ukraine policy as a success, Biden warned that Russia still has a path to victory.

“The world now has another choice to make. Will we sustain our support to help Ukraine win this war and preserve its freedom — or walk away, let aggression be renewed and a nation be destroyed?” Biden told the leaders, including Ukrainian President Volodymyr Zelensky, who sat in the grand hall, unsmiling, a translation headset on his ear.

“I know my answer,” Biden said. “We cannot grow weary. We cannot look away, and we will not let up on our support for Ukraine, not until Ukraine wins a just and durable peace.”

Still, Russia has recently been making gains in Ukraine’s east. With winter looming, some allies of Ukraine fear the country could be pushed into making concessions to Russia to end the war, and Biden is facing pressure to allow American-made missile systems to strike deeper into Russian territory.

Ukrainian leaders have made that policy change a top priority in recent weeks, and many European leaders agree with them. The issue has opened cracks inside the Biden administration, with the Defense Department and White House aides skeptical of the benefits of such a policy shift and Secretary of State Antony Blinken expressing openness on a trip to Kyiv this month.

Zelensky plans to continue to press the issue this week, including at White House meetings with Biden and Harris on Thursday. British Prime Minister Keir Starmer — who also quietly favors a policy shift — plans to continue discussions about it during this week’s U.N. activities in New York.

As he wrapped his speech, Biden reflected on his decision to step aside this summer and end his campaign for a second term. “It was a difficult decision,” Biden said. “Being president has been the honor of my life. There’s so much more I want to get done.”

But he said that after 50 years of public service, he decided it was time for a new generation of leadership. “It’s your people that matter most,” Biden said. “That’s the soul of democracy. It does not belong to any one country.”