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Russia warned Europe to hold back from arming Ukraine as President Vladimir Putin raised some hopes of meeting with his counterpart Volodymyr Zelenskyy as fighting was entering a a third week.
Moscow's Foreign Minister Sergey Lavrov said such talks must have "added value" and not take place "just for the sake of it" as he said the supply of weapons by EU and Nato countries of deadly weapons to Ukraine was "creating a colossal danger for themselves".
He was speaking in Turkey after holding talks with Kyiv's Foreign Minister Dmytro Kuleba, the first meeting between the pair since Russia invaded Ukraine two weeks ago.
Those talks failed to make headway and came after a Russian air strike on a children's hospital in the south-eastern city of Mariupol, an attack described by Mr Zelenskyy as a war crime. Mr Kuleba said his Russian counterpart did not agree to a corridor from Mariupol and there was no progress on ceasefire talks.
Mr Lavrov said that the military operation was going to plan, adding that Moscow is still waiting for a reply to its list of four demands to end the invasion – terms Mr Kuleba said were tantamount to surrender.
"We confirmed today that President Putin doesn't reject meeting President Zelenskyy," Mr Lavrov said "Probably, such a necessity will take place, but for this, we need to undertake preparatory work on the Belarusian track," he said, referring to talks between Ukraine and Russia that have taken place in Belarus.
Mr Kuleba said the two priorities for Kyiv right now were organising humanitarian corridors from Mariupol and reaching a 24-hour truce.
As the ministers were speaking, news from the frontlines indicated an aid convoy for Mariupol was forced to turn around due to Russian shelling.
At least three people were killed in the air strike, including a young girl, local officials said on Thursday. Russia has not denied the attack on the hospital, but Mr Lavrov claimed it was being used as a base for the far-right Azov Battalion. He said there had been "no women, children or service personnel" present there "for a long time".
The air strike on the Mariupol hospital, which officials said contained maternity and paediatric units, blew out windows, ripped down partition walls and set fire to cars parked outside, videos posted by officials showed.
"We have not done and would never do anything like this war crime in any of the cities of the Donetsk or Lugansk regions, or of any region ... because we are people. But are you?" Mr Zelenskyy said on Wednesday night, switching to Russian to make his point.
"What kind of a country is Russia, that it is afraid of hospitals and maternity wards and destroys them?" he said.
Poland's President Andrzej Duda accused Russia of committing war crimes in Ukraine, while US Vice President Kamala Harris backed calls for an investigation into Russian actions during the invasion of Ukraine.
"Pregnant women going for health care being injured by a missile, a bomb in an unprovoked, unjustified war where a powerful country is trying to take over another country, violate its sovereignty, its territorial integrity for the sake of nothing that is justified or provoked," Ms Harris said in Poland alongside Mr Duda.
"Absolutely, there should be an investigation. We should all be watching. I have no question the eyes of the world are on this war and what Russia has done in terms of this aggression and these atrocities."
Mr Duda said that in his view the invasion was “bearing the features of a genocide – it aims at eliminating and destroying a nation”.
Mr Zelenskyy confirmed a figure of 17 wounded, given earlier by a regional official, saying that those in the hospital had "started hiding in time from the air raid signal".
He said that a search of the rubble was ongoing.
Brutal and indiscriminate
The air strike on the hospital came amid growing warnings from the West that Moscow’s offensive is about to take a more brutal and indiscriminate turn.
The ground shook up to two kilometres away when the Mariupol complex was hit by a series of blasts that blew out windows and ripped away much of the front of one building.
Police and soldiers rushed to the scene to rescue victims, carrying out a heavily pregnant and bleeding woman on a stretcher as light snow drifted down on burning and mangled cars and trees shattered by the blast.
Another woman wailed as she clutched her child. In the courtyard, a blast crater extended at least two storeys deep.
“Today Russia committed a huge crime,” said Volodymir Nikulin, a top regional police official, standing in the ruins. “It is a war crime without any justification.”
Meanwhile, workers in Mariupol are hastily and unceremoniously burying scores of dead Ukrainian civilians and soldiers in a mass grave.
With morgues overflowing and more corpses uncollected in homes, city officials decided they could not wait to hold individual burials.
A deep trench about 25 metres long dug in an old cemetery in the heart of the city is filling up with bodies collected by municipal social service workers from morgues and private homes.
Some are brought wrapped in carpets or plastic bags. Forty came on Tuesday, and at least another 30 on Wednesday.
They include civilian victims of shelling on the city and soldiers, as well as civilians who died of disease or natural causes.
Other city workers are also bringing bodies, so the numbers being buried are quickly rising and the total in the long grave is now unclear.
In Zhytomyr, a city of 260,000 to the west of Kyiv, bombs fell on two hospitals, one of them a children’s hospital, Mayor Serhii Sukhomlyn said on Facebook.
No one was wounded, he said.
Tougher sanctions urged
Mr Zelenskyy is urging the West to impose even tougher sanctions, so Russia “no longer has any possibility to continue this genocide”.
“There are few things more depraved than targeting the vulnerable and defenceless,” British Prime Minister Boris Johnson tweeted. He said Russian President Vladimir Putin will be held “to account for his terrible crimes”.
The World Health Organisation said it has confirmed 18 attacks on health facilities and ambulances since the fighting began, killing 10 people.
It was not clear if that number included the assault on the maternity hospital in Mariupol.
US Secretary of State Antony Blinken condemned Russia’s “unconscionable attacks” in a call with his Ukrainian counterpart, Mr Kuleba, the State Department said.
In a joint phone call with Mr Putin before an EU summit, French and German leaders Emmanuel Macron and Olaf Scholz demanded an immediate ceasefire in Ukraine.
Two weeks into Russia’s assault on Ukraine, its military is struggling more than expected, but Mr Putin’s invading force of more than 150,000 troops retains possibly insurmountable advantages in firepower as it bears down on key cities.
Despite often heavy shelling on populated areas, US military officials reported little change on the ground over the past 24 hours, other than Russian progress on the cities of Kharkiv and Mykolaiv.
Authorities announced new ceasefires on Wednesday to allow thousands of civilians to escape bombarded towns around Kyiv, as well as the cities of Mariupol, Enerhodar and Volnovakha in the south, Izyum in the east and Sumy in the north-east.
Out of Kyiv
People streamed out of Kyiv’s suburbs, many headed for the city centre, as explosions were heard in the capital and air raid sirens sounded repeatedly.
From there, the evacuees planned to board trains bound for western Ukrainian regions not under attack.
Civilians leaving the Kyiv suburb of Irpin were forced to make their way across the slippery wooden planks of a makeshift bridge, because the Ukrainians blew up the concrete span leading to Kyiv days ago to slow the Russian advance.
With sporadic gunfire echoing behind them, firefighters dragged an elderly man to safety in a wheelbarrow, a child gripped the hand of a helping soldier, and a woman inched her way along, cradling a fluffy cat inside her winter coat. They trudged past a crashed van with the words “Our Ukraine” written in the dust coating its windows.
“We have a short window of time at the moment,’’ said Yevhen Nyshchuk, a member of Ukraine’s territorial defence forces. “Even if there is a ceasefire right now, there is a high risk of shells falling at any moment.”
Previous attempts to establish safe evacuation corridors over the past few days largely failed because of what the Ukrainians said were Russian attacks. But Mr Putin, in a telephone call with Germany’s chancellor, accused militant Ukrainian nationalists of hampering the evacuations.
The Ukrainian military, meanwhile, is building up defences in cities in the north, south and east, and forces around Kyiv are “holding the line” against the Russian offensive, authorities said.
On Wednesday, some of Ukraine’s volunteer fighters trained in a Kyiv park with rocket-propelled grenade launchers.
“I have only one son,” said Mykola Matulevskiy, 64, a retired martial arts coach, who was with his son, Kostyantin. “Everything is my son.”
In Irpin, a town of 60,000, police officers and soldiers helped elderly residents from their homes. One man was hoisted out of a damaged structure on a makeshift stretcher, while another was pushed towards Kyiv in a shopping cart. Fleeing residents said they had been without power and water for the past four days.
Regional administration head Oleksiy Kuleba said the crisis for civilians is deepening in and around Kyiv, with the situation particularly dire in the suburbs.