GEOFF BENNETT: Welcome to the "NewsHour."

The annual United Nations General Assembly met today, with the world, in the words of Secretary-General Antonio Guterres, at the point of a -- quote -- "great fracture."

AMNA NAWAZ: He wasn't the only one with an unsparing view of the myriad problems faced by many nations.

President Biden spoke this morning, and sought to reassure underdeveloped nations that the U.S. will help them through these tough times.

But his most forceful words were reserved for Russia and its war against Ukraine.

White House correspondent Laura Barron-Lopez begins our coverage.

LAURA BARRON-LOPEZ: The General Assembly gathered today under dark clouds of war, climate crisis, and inequality.

Secretary-General Antonio Guterres was blunt.

ANTONIO GUTERRES, United Nations Secretary-General: Our world is becoming unhinged.

Geopolitical tensions are rising.

Global challenges are mounting.

And we seem incapable of coming together to respond.

LAURA BARRON-LOPEZ: One hundred and forty-five world leaders were set to address the group.

But leaders from Britain, France, China, and Russia were absent.

JOE BIDEN, President of the United States: As president of the United States, I understand the duty my country has to lead in this critical moment.

LAURA BARRON-LOPEZ: Making the United States the only permanent Security Council member with veto power to address the body.

(APPLAUSE) LAURA BARRON-LOPEZ: President Biden drew applause after he denounced Russia's war as Ukrainian President Volodymyr Zelenskyy looked on.

JOE BIDEN: If you allow Ukraine to be carved up, is the independence of any nation secure?

I would respectfully suggest the answer is no.

We have to stand up to this naked aggression today and deter other would-be aggressors tomorrow.

LAURA BARRON-LOPEZ: Yesterday, Zelenskyy visited wounded Ukrainian soldiers at a hospital in New York.

He criticized the U.N. for still including Russia and its ranks.

VOLODYMYR ZELENSKYY, Ukrainian President: If in the United Nations still, it's a pity, but, still, there is a place for Russian terrorists, it's a question not to me, I think.

It's a question to all the members of the United Nations.

LAURA BARRON-LOPEZ: This year was Zelenskyy's first in-person appearance at the General Assembly.

VOLODYMYR ZELENSKYY: While Russia is pushing the world to the final war, Ukraine is doing everything to ensure that, after Russian aggression, no one in the world will dare to attack any nation.

Weaponization must be restrained.

War crimes must be punished.

Deported people must come back home.

And the occupier must return to their own land.

We must be united to make it.

And we will do it.

Slava Ukraini.

(APPLAUSE) LAURA BARRON-LOPEZ: Even as Biden pledged support in New York, back in Washington, House Republicans are rejecting more aid for Ukraine.

Speaker Kevin McCarthy was asked if more money was on the way.

REP. KEVIN MCCARTHY (R-CA): Is Zelenskyy elected to Congress?

Is he our president?

I don't think I have to commit anything.

I have questions for him.

Where is the accountability in the money we already spent?

What is the plan for victory?

LAURA BARRON-LOPEZ: At an air base in Germany today, U.S. military officials addressed reporters on the state of the war.

Defense Secretary Lloyd Austin and Joint Chiefs Chair Mark Milley took part in a meeting of the Ukraine Defense Contact Group.

GEN. MARK MILLEY, Chairman, Joint Chiefs of Staff: This counteroffensive has been going on for about 90 days, and it is taking longer than planners in the war games, et cetera, with the Ukrainian planners and the war games, anticipated.

But that's the difference between war on paper and real war.

There are real human beings in real vehicles moving across real minefields getting blown up, killed, wounded, et cetera.

LAURA BARRON-LOPEZ: The flames of war burn on in Ukraine.

Last night, Russia launched a drone attack that set warehouses containing food and other supplies on fire and killed one person in the western city of Lviv.

For the "PBS NewsHour," I'm Laura Barron-Lopez.