Fresh attacks on civilians have fuelled accusations that Russia is committing war crimes in Ukraine, as the United States warned it will make China pay for any support given to Moscow's assault.
Three weeks into Russia's devastating invasion, the harsh tally of assaults on civilian targets grew to include a school and a cultural centre in the town of Merefa, pounded by overnight artillery fire with 21 people killed, authorities said.
Despite the mounting carnage, punishing international sanctions and unexpectedly strong resistance from Ukrainians, the United States' top diplomat Antony Blinken said on Thursday he saw no sign that Russian leader Vladimir Putin "is prepared to stop".
"Intentionally targeting civilians is a war crime. After all the destruction of the past few weeks, I find it difficult to conclude that the Russians are doing otherwise," he said, following warnings from the G7 that those behind such crimes "will be held responsible".
Mr Blinken was doubling down on the tough language used by President Joe Biden - who a day earlier branded Mr Putin a "war criminal" and on Thursday called him both a "thug" and a "murderous dictator".
“Now you have Ireland and Great Britain and, you know, the Republic standing together against a murderous dictator, a pure thug who is waging an immoral war against the people of Ukraine,” Mr Biden said during a St Patrick's Day speech at the US Capitol.
Smoke and flames rise as a fire broke out after Russian rockets hit warehouses in Sviatoshynskyi district, Kyiv, Ukraine on 17 March, 2022. Source: Getty / Anadolu Agency
In the latest of a series of resonant speeches to Western lawmakers, Mr Zelenskyy told the German parliament that Moscow was building a new Cold War wall across Europe, "between freedom and bondage".
Russia's unrelenting onslaught on Mariupol has drawn particular horror.
Local officials say more than 2,000 people have died so far in indiscriminate Chechnya-style shelling of the strategic port, and 80 per cent of its housing has been destroyed.
Under new Russian shelling, rescuers were combing through the smoking rubble of the Drama Theatre, where Ukrainian officials said more than 1,000 civilians were sheltering in a basement bomb shelter when it was bombed. Human Rights Watch believes they numbered at least 500.
The Drama Theatre in Mariupol, Ukraine, where residents were sheltering was destroyed after it was bombed on Wednesday. Source: AAP / AP
"In the streets there are the bodies of many dead civilians," Tamara Kavunenko, 58, told news agency AFP after reaching the central city of Zaporizhzhia.
"It's not Mariupol anymore," she said. "It is hell."
US puts China on notice
Mr Biden and NATO have refused to get directly involved in the conflict, fearing an escalation with nuclear-armed Russia that would trigger World War Three.
Instead, Mr Biden has successfully marshalled a tight Western alliance against Moscow, piling sanctions on Mr Putin's regime while giving military support to Ukrainian forces.
But one potentially dangerous outlier looms: China.
Beijing has refused to condemn Moscow, and Washington fears the Chinese could switch to full financial and even military support for Russia, transforming an already explosive transatlantic standoff into a global dispute.
Mr Blinked on Thursday said the US is concerned that Beijing is "considering directly assisting Russia with military equipment to use in Ukraine".
A woman stands next to a damaged building in the aftermath of shelling in Kharkiv, Ukraine, on 17 March 2022. Source: AAP, EPA / Vasiliy Zhlobsky
Mr Biden "will make clear that China will bear responsibility for any actions it takes to support Russia's aggression and we will not hesitate to impose costs," Mr Blinken said.
The broader economic consequences of the war could cut global growth by "over one percentage point" in the next 12 months, the Organisation for Economic Cooperation and Development said.
But Russia's finance ministry said Thursday it had made interest payments worth $117.2 million ($159 million) on two foreign bonds, avoiding a default for now.
'Tear down this wall'
With stop-start peace talks ongoing, officials in Kyiv said Russia had agreed to nine humanitarian corridors Thursday for fleeing refugees, including one out of Mariupol.
But Mr Blinken said that Moscow was not sincere, stating: "I have not seen any meaningful efforts by Russia to bring this war that it is perpetrating to a conclusion through diplomacy."
As the death toll mounts and Russian forces squeeze Kyiv, Mr Zelenskyy continued his increasingly desperate pleas for more help, particularly for military hardware and a no-fly zone.
Ukrainian President Volodymyr Zelenskyy addressed the German parliament in Berlin, Germany, on 17 March 2022, via videolink. Source: AAP, EPA / Clemens Bilan
This time, before the German parliament, he drew on a 1987 speech in Berlin by US president Ronald Reagan: "Dear Mr Scholz, tear down this wall," he implored German Chancellor Olaf Scholz.
"It's not a Berlin Wall — it is a wall in central Europe between freedom and bondage and this wall is growing bigger with every bomb."
In an overnight video message, Mr Zelenskyy urged Russians directly to lay down their arms.
"If your war, the war against the Ukrainian people, continues, Russia's mothers will lose more children than in the Afghan and Chechen wars combined," he said.
'Hundreds' of civilians now dead
More than 700 civilians, including 52 children, have been killed in Ukraine since Russia invaded three weeks ago, but the "actual number is likely much higher", United Nations political affairs chief Rosemary DiCarlo has told the Security Council.
"Most of these casualties were caused by the use in populated areas of explosive weapons with a wide impact area. Hundreds of residential buildings have been damaged or destroyed, as have hospitals and schools," Ms DiCarlo said on Thursday.
She told the 15-member council the UN human rights agency has recorded 726 deaths, including 52 children, and 1,174 people injured, including 63 children, between 24 February and 15 March. Ms DiCarlo did not specify who was to blame.
A market in a residential area that was destroyed by Russian forces in Kharkiv, Ukraine, on 17 March, 2022. Source: Getty / Anadolu Agency
The World Health Organisation (WHO) has verified 43 attacks on health care in Ukraine that have killed 12 people and injured dozens more, including health workers, WHO Director-General Tedros Adhanom Ghebreyesus told the Security Council.
"In any conflict, attacks on health care are a violation of international humanitarian law," Dr Tedros told the council, without specifying who was to blame.
The Security Council is due to vote on Friday on a Russian-drafted call for aid access and civilian protection in Ukraine, but diplomats say the measure is set to fail because it does not push for an end to the fighting or withdrawal of Russian troops.
'It is hell'
The Ukrainian leader was speaking virtually from Kyiv, which Russian troops are still trying to surround in a slow-moving offensive.
Fresh fighting broke out on the city's edge as Ukrainian and Russian forces traded shell and rocket fire in the northwest, AFP journalists witnessed.
Civilians ran for cover as shelling set fire to a building near a warehouse, across the road from a mall with a multiplex cinema.
Inside the warehouse's car park, a Ukrainian soldier carrying a rifle ran in a crouch as gunshots crackled.
A man carried a prone child in his arms into a nearby block of flats, and at least five ambulances raced towards the scene.
Civilians follow a humanitarian corridor from the besieged city of Mariupol, Ukraine, on 17 March, 2022. Source: AP, SIPA USA / TASS
"Our beautiful Odesa," said Lyudmila, an elegant elderly woman wearing bright lipstick, as she looked apologetically at her city's empty, barricaded streets.
"But thank God we are holding on! Everyone is holding on!"
And elsewhere, civilians in bomb shelters did what they could to help forget the war raging outside - even just for a while.
From her shelter in Ukraine's second city Kharkiv, Vera Lytovchenko has become a social media sensation with her violin performances and used the attention to launch a fundraiser.
"I want to help my friends and music teachers who have lost their homes, their jobs, their instruments," said the soloist.
"I don't want to feel helpless," she said.
