Ukraine accused Russia of conducting state-sponsored kidnapping of children, Ukrainian Foreign Minister Dmytro Kuleba said in a statement to the United Nations Security Council on Friday.

"The magnitude of the humanitarian crisis brought on by Russia's aggression against Ukraine cannot be overstated. I would like to highlight here one of numerous horrendous facts - Russia is now implementing in Ukraine probably the largest instance of state sponsored kidnapping of children in history of our modern world," Kuleba said.

-ABC News' Ellie Kaufman

Ukrainian President Volodymyr Zelenskyy told reporters he wants to believe China won’t supply Russia with weapons in the ongoing conflict.

NATO Secretary General Jens Stoltenberg and U.S. Secretary of State Antony Blinken said Thursday that the U.S. and NATO have intelligence that China is getting ready to possibly supply Russia with weapons. China has denied these claims.

Zelenskyy said it is "priority No. 1" for him to prevent China from providing Russia with weapons.

"This is very important. This is priority No. 1 for me and I am doing my best to prevent that from happening. It is important for us," he said.

He added, "I believe China is going to side with the idea of fair peace, peace and fairness which is our side."

-ABC News' Fidel Pavlenko

One year ago, with Ukraine's borders surrounded by what seemed to be a superior military force, many U.S. officials and analysts predicted a swift Russian blitz to Kyiv.

But after Russian President Vladimir Putin sent his more than 150,000 arrayed troops across the border, it soon became clear that a dual reassessment was in order: The Russian invaders were less potent than advertised, and the Ukrainians were unexpectedly stubborn and wily in the defense.

Some of the Russian troops weren’t even aware they were on a combat mission until Ukrainian bullets came cracking past them, according to U.S. officials. Meanwhile, Ukrainian forces stalled a massive Russian supply convoy through direct attacks and by destroying a key bridge. Only one week into the invasion, Putin's men were plagued with food and fuel shortages, morale running similarly low.

Kyiv stood.

"Putin assumed that Ukraine was an easy target, Putin assumed that Kyiv would easily fall, and Putin assumed that the world would stand by," U.S. Secretary of Defense Lloyd Austin said during a speech in Brussels last week. "But the Kremlin was wrong on every count."

Ukrainian forces were armed with more than grit.

They also had years of U.S. and NATO military training, plus American-made weapons, like anti-armor Javelins and anti-aircraft Stinger missiles. These made Russian vehicles vulnerable to ambush, and left Russian helicopter and jet pilots wary of flying over Ukrainian positions. Indeed, many airmen did not return from their sorties.

Despite astonishing losses of soldiers and vehicles, Putin has shown no inclination to end the conflict anytime soon. And despite its tenacity, Ukraine has also taken significant casualties, and is not able to produce enough of its own weapons and ammunition to keep up the fight.

Ukraine, after thwarting the advance on its capital, and later routing Russian forces from Kharkiv, now largely faces a battle of supply.

"When this war began, Russia had a larger population, a much bigger defense budget, a bigger military, bigger industrial base. So, this became an industrial war and a war of industrial bases," said Seth Jones, director of the International Security Program at the Center for Strategic and International Studies. "This is why Western industrial support has been so critical."

A key question now is, despite massive military aid packages and a promise to send even more, could the U.S. strategy ultimately result, not in a Ukrainian victory, but a stalemate in a years-long war of attrition?

-ABC News' Matt Seyler

Asked if he believes in victory, Ukrainian President Volodymyr Zelenskyy said his country "definitely" will if fellow nations keep their word about help and aid.

"Luckily, we’re not alone, so all of us should stay focused," Zelenskyy said.

Zelenskyy also said Ukraine has "put forward its peace plan, peace formula," which is "supported by many nations."

Rather than having bilateral peace negotiations, Zelenskyy suggested a "peace forum with participation of many countries from different continents."

"I’d like to see China, India, other countries approving post-war security guarantees," Zelenskyy said.

-ABC News' Fidel Pavlenko

Russia’s Wagner mercenary group said it will retreat from Bakhmut because of severe shortages in ammunition, according to Yevgeny Prigozhin, the group's leader. He said his forces would withdraw on May 10, blaming Russia’s defense ministry for the retreat.

Wagner has played a crucial role for months in the fighting for Bakhmut, sustaining huge casualties. The announcement and the suggestion of bitter infighting within Russia’s military forces signals division and disorganization just as Russia is bracing for a major Ukrainian counteroffensive.

Prigozhin said he was taking the decision in retaliation against Russia’s military leadership, which he accused of deliberately starving his troops of ammunition because they are jealous of Wagner’s success.

Prigozhin and Russia’s defense ministry have been in a one-sided public feud for months. Prigozhin claims it's now reached a breaking point, delivering a blistering attack on Russia's senior military command in the video announcing the withdrawal. He accused them of being "cowards" and of denying Russians a victory in Bakhmut because of their "petty envy."

Ukrainian military officials said they did not believe Wagner forces would retreat from Bakhmut, suggesting they believed his announcement was an attempt to excuse his failure to seize the city by May 9 as he pledged. A spokesman for Ukraine's eastern command, Sergiy Cherevatyi, said Wagner was running out of fighters, not ammunition.

-ABC News' Patrick Reevell