Ukraine has called on China to join the West in condemning "Russian barbarism", as Russia claimed it had struck a Ukrainian arms depot with hypersonic missiles in what would be the first use in combat of the next-generation weapons.
That attack, not far from the Romanian border in the west, came as Russia said its troops had broken through Ukrainian defences to enter the besieged southern port city of Mariupol, a scene of mounting desperation.
With the invasion in its fourth week, Kyiv's embattled leader Volodymyr Zelenskyy pressed for "meaningful" talks to halt fighting that has forced at least 3.3 million Ukrainians to flee their country.
The plea for China to condemn the invasion came from a top Zelenskyy advisor, Mikhailo Podolyak.
China could play an important role in global security, he said on Twitter, "if it makes a right decision to support the civilised countries' coalition and condemn Russian barbarism".
While Western countries have shown unity in the face of an invasion whose brutality has been clearly documented on social media, China has so far refused to condemn it.
Russia's claim Saturday to have unleashed its new hypersonic Kinzhal missile would mark a dramatic new escalation of its campaign to force Ukraine to abandon hopes of closer ties with the West.
Ukrainian air force spokesman Yuri Ignat told AFP that the arms depot in the western village of Deliatyn had indeed been hit but "we have no information of the type of missile".
Hypersonic weapons can travel faster than five times the speed of sound and the Interfax agency said it was the first time Russia had used them in Ukraine.
Russian President Vladimir Putin, who unveiled the Kinzhal missile in 2018, has termed it "an ideal weapon" that flies at 10 times the speed of sound, making it extremely difficult for missile defences to intercept.
Mr Putin, who calls the action in Ukraine a "special operation" aimed at demilitarising the country and purging it of what he sees as dangerous nationalists, told a rally on Friday in Moscow that all the Kremlin's aims would be achieved.
In another setback, Ukraine officials admitted they had "temporarily" lost access to the Sea of Azov, though Russia has effectively controlled the coastline for weeks after surrounding Mariupol.
'Time to talk'
, urging Russia to accept "meaningful" talks in his latest video posted on social media.
"This is the time to meet, to talk, time for renewing territorial integrity and fairness for Ukraine," he said.
"Otherwise, Russia's losses will be such that several generations will not recover."
President Volodymyr Zelenskyy speaks from Kyiv, Ukraine, early Saturday, 18 March 18, 2022. Credit: AP
Ukrainian cities "are being destroyed on the orders of people who live in European, in beautiful Swiss towns, who enjoy property in your cities. It would really be good to strip them of this privilege," he said in an audio address.
Neutral Switzerland, which is not a member of the European Union, has fully adopted EU sanctions against Russian individuals and entities, including orders to freeze their wealth in Swiss banks.
The EU measures are part of a wider sanctions effort by Western nations, criticised by China, aimed at squeezing Russia's economy and starving its war machine.
There appears to be little progress in reaching a ceasefire, with Mr Putin accusing Ukraine of "numerous war crimes" during a call late Friday with French President Emmanuel Macron.
British intelligence warned that Russia, frustrated by its failure to achieve its objectives since it launched the invasion on 24 February, was now pursuing a strategy of attrition that could intensify the humanitarian crisis.
British Foreign Secretary Liz Truss said Saturday that Moscow was using the talks as a "smokescreen" as it carried out "appalling atrocities".
Fierce resistance has managed to stall Russian forces outside Kyiv and several other cities in the east, making them vulnerable to Ukrainian attacks against supply lines.
Ukraine claimed Saturday that a Russian general had been killed by strikes on an airfield outside Kherson, just north of Crimea, saying he was the fifth top-ranking officer killed since the invasion began.
Britain's defence ministry said Saturday that Russia has been forced to "change its operational approach and is now pursuing a strategy of attrition."
"This is likely to involve the indiscriminate use of firepower resulting in increased civilian casualties," it warned.
A displaced family from Kyiv, right, sit in a basement, used as a bomb shelter, during an air raid in Lviv, Western Ukraine. Source: AAP / Bernat Armangue/AP
'Extremely dire' situation in Mariupol, UN warns
Friday's attack on the arms depot was the latest strike in western Ukraine, which until a few days ago had remained relatively unscathed by Russia's push toward key cities from the north and east.
Also on Friday, Russian forces destroyed an aircraft repair plant near the airport of Lviv, the city where millions of people have fled as rockets and shelling continue to rain down on Kyiv.
Russian rockets also struck Mykolaiv in the south on Friday, killing dozens of young Ukrainian ensigns at their brigade headquarters.
"No fewer than 200 soldiers were sleeping in the barracks" at the time, a Ukrainian serviceman on the ground, 22-year-old Maxim, told AFP.
"At least 50 bodies have been recovered, but we do not know how many others are in the rubble," he said.
In Mariupol, rescuers were still searching for hundreds of people trapped under the wreckage of a bombed theatre where over 1,000 people had been seeking shelter when it was struck on Wednesday.
There was still no information about potential fatalities, Mr Zelenskyy said, but 130 people had been saved so far, some "heavily injured."
"This is no longer Mariupol, it's hell," said resident Tamara Kavunenko, 58. "The streets are full with the bodies of civilians."
After weeks cut off from food, water and electricity, the situation in Mariupol has become "extremely dire," the UN refugee agency said Friday.
The UN human rights office said at least 847 civilians had been killed and 1,399 wounded in Ukraine as of Friday, with the real figure likely much higher. The Ukrainian prosecutor general's office said 112 children were among the dead. Russia says it is not targeting civilians.
Kyiv authorities said on Saturday that 228 people had been killed in the capital since Russia's invasion began, including four children.
A further 912 people have been wounded, the Kyiv city administration said in a statement.
Reuters has not been able to independently confirm casualty figures.
Appeals to China
Russia's ally China told US President Joe Biden on Friday that the war was "in no one's interest," but showed no sign of giving in to the pressure to join Western condemnation of Russia.
Mr Biden warned his Chinese counterpart Xi Jinping of "consequences" for any financial or military aid for Russia, a move that could turn the standoff into a global confrontation.
Mr Putin appears undeterred by further threats or sanctions, holding a triumphalist rally in Moscow on Friday to mark eight years since Russia's seizure of Crimea, saying his goal in Ukraine was "to rid these people from their suffering and genocide."
Russia wants Ukraine to disarm and disavow all Western alliances, in particular to renounce joining NATO or to seek closer integration with the European Union -- steps that Kyiv says would turn it into a vassal state of Moscow.
Russia's top negotiator said Friday that Moscow and Kyiv had brought their positions "as close as possible" on a proposal for Ukraine to become a neutral state.
But Mr Podolyak, the Zelenskyy advisor, said his country's position had not budged.
'Know how to fight'
Ordinary Ukrainians have joined the effort to defend their country, such as at a training facility in Odessa, a picturesque, multicultural Black Sea port, where young urban professionals were learning about handling weapons and applying first aid.
"Every person should know how to fight, how to make medicine," said 26-year-old graphic designer Olga Moroz.
More than 3.3 million refugees have fled Ukraine through its western border, with around two more million displaced inside the country. Ukraine has evacuated 190,000 civilians from frontline areas via humanitarian corridors, Deputy Prime Minister Iryna Vereshchuk said on Saturday.
"I'll go (to Germany) for three weeks but I hope I can go home after that," said Olga Pavlovska, a 28-year-old refugee in the Polish town of Przemysl, hoping Mr Zelekskyy's calls for comprehensive peace talks will end the invasion.
A view of destroyed theatre hall, which was used as a shelter by civilians, after Russian bombardment in Mariupol, Ukraine on 18 March 2022. Source: Getty / Anadolu Agency/Anadolu Agency via Getty Images
About 600 residential buildings in the eastern Ukrainian city of Kharkiv have been destroyed and are unfit for habitation since the start of the Russian invasion, Kharkiv's regional governor Oleh Synyehubov said.
Rescue workers were still searching for survivors in a Mariupol theatre that authorities say was flattened by Russian air strikes on Wednesday. Russia denies hitting the theatre.
Interfax quoted Russian Foreign Minister Sergei Lavrov as saying Moscow expected its operation in Ukraine to end with a signing of a comprehensive agreement on security issues, including Ukraine's neutral status.
Kyiv and Moscow reported some progress in talks this week towards a political formula that would guarantee Ukraine's security, while keeping it outside NATO, though both sides accused each other of dragging things out.
