Fighting is raging on multiple fronts in Ukraine, with intense combat underway in the besieged port city of Mariupol — the site of some of the war's greatest suffering. Ukrainian officials say their forces there are battling the Russians over the Azovstal steel plant, one of the biggest in Europe.
Overnight, Ukrainian President Volodymyr Zelenskyy accused the Kremlin of deliberately creating "a humanitarian catastrophe," but also appealed for Russian President Vladimir Putin to meet him for direct talks.
The U.N. migration agency says nearly 6.5 million people have been displaced inside Ukraine, along with the 3.3 million refugees who have already fled the country. Ukraine says thousands have been killed.
Here are some key things to know about the conflict:
WHAT IS HAPPENING ON THE GROUND?
In Mariupol, Ukrainian troops were losing control of the key Azovstal steel plant, now damaged and heavily contested, according to an adviser to Ukraine's interior minister.
"We have lost this economic giant. In fact, one of the largest metallurgical plants in Europe is actually being destroyed," Vadym Denysenko said in televised remarks.
An adviser to Ukraine's president said there was no military solution to Mariupol, saying the nearest forces able to assist were already struggling against Russian forces at least 60 miles away.
Zelenskyy said in his Friday nighttime video address to the nation that more than 9,000 people were able to leave Mariupol in the past day, and in all more than 180,000 people have been able to flee through 10 humanitarian corridors that have been agreed on with the Russians.
The corridors announced Saturday include one from Mariupol, several in the region of the capital, Kyiv, and in the Luhansk region. Humanitarian aid deliveries are also planned for the city of Kherson, currently under Russian control.
In a statement, the Mariupol city council said Russian soldiers have forced several thousand residents of the city to leave and be relocated to Russia.
A 38-hour curfew was announced in the southeastern city of Zaporizhzhia, to last from 4 p.m. on Saturday until 6 a.m. Monday. Officials said two missile strikes on the city's suburbs a day earlier killed nine people. Local authorities there say they continue to evacuate people from areas occupied by Russian troops.
The Russian military reported Saturday that it has used its latest hypersonic missile for the first time in combat. A spokesman for the Russian Defense Ministry, Maj. Gen. Igor Konashenkov, said Kinzhal missiles destroyed an underground warehouse storing Ukrainian missiles and aviation ammunition in the western Ivano-Frankivsk region of Ukraine.
Pentagon press secretary John Kirby said Saturday the U.S. cannot confirm the Russians used a hypersonic missile in the attack.
WHAT ARE WORLD LEADERS DOING?
President Joe Biden and China's Xi Jinping spoke Friday for nearly two hours via video as the U.S. looks to deter Beijing from providing military or economic aid for Russia's invasion. President Biden described the consequences the Chinese would face from the U.S. if they provide military or economic assistance for Russia's invasion of Ukraine. For his part, Xi urged the U.S. and Russia to negotiate and blamed the U.S. for the crisis.
On Saturday, China's vice foreign minister reiterated blame against NATO for the war, and criticized sanctions against Russia. Le Yucheng said NATO was a "Cold War vestige" and that its expansion could result in "repercussions too dreadful to contemplate" from a major power like Russia.
Speaking to a Conservative Party conference, British Prime Minister Boris Johnson said Russia's invasion of Ukraine is a "turning point for the world," arguing that victory for President Vladimir Putin's forces would herald "a new age of intimidation." Johnson said a loss of freedom in Ukraine would mean "the extinction of any hope of freedom in Georgia and then Moldova."
President Biden plans to travel to Europe next week for talks with European leaders about the Russian invasion, and will attend an extraordinary NATO summit in Brussels.
HOW ARE REFUGEES FARING?
Thousands of refugees from Ukraine waited in long lines in the Polish capital of Warsaw to receive local identification papers that will allow them to move on with their lives.
Refugees started queuing by Warsaw's National Stadium overnight to get the coveted PESEL identity cards that will allow them to work, live, go to school and get medical care or social benefits for the next 18 months.
By mid-morning Saturday, many were told to come back another day because the demand was too high even though Polish authorities had simplified the process.
Poland has taken in more than 2 million refugees from Ukraine since Russia invaded on Feb. 24 — the bulk of more than 3.3 million people that the U.N. says have fled since Russia invaded Ukraine on Feb. 24. Hundreds of thousands have streamed into Hungary, Slovakia, Moldova and Romania.
A bipartisan delegation of U.S. lawmakers visiting Poland stopped by the receptions centers Saturday. The seven-member group led by Rep. Stephen Lynch, a Massachusetts Democrat, complimented the willingness of the Polish people to accept refugees. Some Poles have even welcomed refugees into their homes.
During an online meeting with the media, the American lawmakers stressed the need to urgently assist Ukraine's military in their fight against Russian forces.
WHERE DO RUSSIAN-UKRAINE TALKS STAND?
The head of the Russian delegation in talks with Ukrainian officials says the parties have come closer to an agreement on a neutral status for Ukraine — one of the key Russian demands as its offensive continues. Vladimir Medinsky said Friday that the sides also have narrowed their differences on the issue of Ukraine dropping its bid to join NATO.
But Mikhailo Podolyak, an adviser to Zelenskyy, tweeted: "Our positions are unchanged. Ceasefire, withdrawal of troops & strong security guarantees with concrete formulas."
Britain's foreign secretary meanwhile accused Putin of using the talks as a "smokescreen" while he ramps up violence against the country. Liz Truss told the Times of London newspaper that she was "very skeptical" about Russia's seriousness in the talks, accusing Russian forces of trying to create space to regroup and unblock their stalled campaign.
WHAT IS THE CIVILIAN TOLL IN THE WAR SO FAR?
The U.N. human rights office says that it has recorded a total of 816 civilians killed and 1,333 injured since the Russian invasion began on Feb. 24, though it believes the figures vastly understate the actual toll.
The office of the country's Prosecutor General reported Saturday that a total of 112 children have been killed since the start of the fighting. More than 140 children have been wounded.
Dozens of civilians were killed and injured as a result of attacks over the past 24 hours in the eastern Donetsk region, Ukrainian police said Saturday. At least 37 residential buildings and infrastructure facilities were damaged in the attacks, on eight cities and villages using aviation, rocket and heavy artillery.
From Mariupol, police officer Michail Vershnin pleaded from a rubble-strewn street in a video addressed to Western leaders. "Children, elderly people are dying. The city is destroyed and it is wiped off the face of the earth," he said.
HOW IS THE WORLD RESPONDING TO THE WAR?
The United States and its allies have put a slew of sanctions in place aimed at crippling the Russian economy. Hundreds of international companies have announced that they are curtailing operations in Russia, and those who remain are under pressure to pull out.
Aid agencies are ramping up their efforts to deliver relief supplies to civilians affected by the fighting and refugees who have fled Ukraine. The Polish city of Rzeszow, about 60 miles from the Ukrainian border, has become a humanitarian hub for the region.
Additional reporting by The Associated Press.