Ukrainian President Volodymyr Zelenskyy has told global business leaders the world must increase sanctions against Russia to deter other countries from using "brute force" to achieve their aims.
Mr Zelenskyy spoke via video link to the World Economic Forum in Davos as the Ukrainian military claimed to have held off a Russian assault on Sievierodonetsk, an eastern city that has become the main target of a Russian offensive after the surrender of the southern port city of Mariupol last week.
He also revealed Ukraine's worst military losses from a single attack of the war on Monday, saying 87 people had been killed last week when Russian forces struck a barracks housing troops at a training base in the north.
Previously, Ukraine had said eight people died in the 17 May strike on the barracks in the town of Desna.
In the first of what could be many war crimes trials arising from Russia's February 24 invasion, a court in Kyiv sentenced a young Russian tank commander to life in prison for killing an unarmed civilian.
Ukraine prosecutor general Iryna Venediktova said about 13,000 cases of Russian alleged war crimes were being investigated.
Russia has denied targeting civilians or involvement in war crimes while it carries out what it calls a "special military operation" in Ukraine.
With the conflict about to enter its fourth month, Mr Zelenskyy urged countries to put more pressure on Russia and accused them of not exhausting sanctions.
"The sanctions should be maximum, so that Russia - and every other potential aggressor who wants to wage a brutal war against its neighbour - clearly knows the immediate consequences of their actions," he told the Davos meeting.
German foreign minister Annalena Baerbock, right, and Ukrainian prosecutor general Iryna Venediktova talk as they stand near a mass grave in Bucha, on the outskirts of Kyiv, Ukraine, 10 May 2022. Source: AP / Efrem Lukatsky/AP
US Secretary of Defence Lloyd Austin said on Monday that 20 countries have approved weapons shipments to Ukraine.
Greece, Italy and Poland had all agreed to send artillery systems, Mr Austin said, while Denmark had promised missiles and assistance with training had been promised by several others.
He added that the group of countries supporting Ukraine with arms had grown since its initial meeting last month in Germany, with Austria, Bosnia-Herzegovina, Colombia and Ireland now also participating, bringing its membership to 47.
A next meeting has been set for 15 June, on the sidelines of a meeting of NATO defence ministers.
Russia has focused its offensive on the eastern Donbas region since its troops were driven out of the area around the capital Kyiv and the north at the end of March.
Having captured Mariupol last week after a three-month siege, Russian forces now control a largely unbroken swathe of the east and south, freeing up more troops to join the main Donbas fight.
Russia is trying to encircle Ukrainian forces and fully capture the Luhansk and Donetsk provinces that make up the Donbas and where it backs separatist forces.
Ukraine said Russian forces had tried to storm Sievierodonetsk but were unsuccessful and retreated.
The city lies in the easternmost part of a Ukrainian-held pocket of the Donbas and one of the last areas of Luhansk still outside Russia's grip.
Servicemen of the People's Militia of the Donetsk People's Republic in Mariupol which is controlled by the Donetsk People's Republic. Credit: TASS/Sipa USA
The head of the Russian-backed separatists in Donetsk, Denis Pushpin, said on Monday Ukrainian prisoners of war captured at the Azovstal steel-works in Mariupol could also face tribunals.
"Now, they are being kept on the territory of the Donetsk People's Republic. It is planned to organise an international tribunal later."
In other developments, a Russian diplomat at the country's permanent mission at the United Nations in Geneva said he was leaving his post because of his disagreement with the invasion of Ukraine, a rare political resignation over the war.
Boris Bondarev, who identified himself on LinkedIn as a counsellor who worked on arms control, told Reuters: "The scale of this disaster drove me to do it."
"I simply cannot any longer share in this bloody, witless and absolutely needless ignominy."
Russian soldier sentenced to life in prison for war crimes
A Ukrainian court sentenced a Russian soldier to life in prison on Monday for killing an unarmed civilian in the first war crimes trial arising from Russia's 24 February invasion.
Vadim Shishimarin, a 21-year-old tank commander, had pleaded guilty to killing 62-year-old Oleksandr Shelipov in the northeastern Ukrainian village of Chupakhivka on 28 February after being ordered to shoot him.
Judge Serhiy Agafonov said Shishimarin, carrying out a "criminal order" by a soldier of higher rank, had fired several shots at the victim's head from an automatic weapon.
"The court has decided: Shishimarin Vadim Evgenyevich ... is found guilty ... and sentenced him to life imprisonment," he said.
"Given that the crime committed is a crime against peace, security, humanity and the international legal order ... the court does not see the possibility of imposing a (shorter) sentence of imprisonment on Shishimarin for a certain period."
Russian serviceman Vadim Shishimarin sits in the dock on the second day of his war crimes trial in the Solomyansky district court in Kyiv, Ukraine on 19 May, 2022. Source: EPA / OLEG PETRASYUK/EPA
For much of the time, he stood with head bowed as he listened to a translator who stood with two guards outside the reinforced glass box.
The trial has huge symbolic significance for Ukraine, which has accused Russia of atrocities and brutality against civilians during the invasion and said it has identified more than 10,000 possible war crimes.
Russia has denied targeting civilians or involvement in war crimes.
The Kremlin did not immediately comment on the verdict. It has previously said that it has no information about the trial and that the absence of a diplomatic mission in Ukraine limits its ability to provide assistance.
Ukrainian state prosecutors said Shishimarin and four other Russian servicemen stole a privately owned car to escape after their column was targeted by Ukrainian forces. The soldiers then drove into the village of Chupakhivka where they saw Shelipov riding a bicycle and talking on his phone, they said.
The prosecutors said Shishimarin was ordered by another serviceman to kill the civilian to prevent him reporting on the Russians' presence and he fired several shots through the open window of the car with an assault rifle at Shelipov's head. Shelipov died on the spot.
In court last week, Shishimarin acknowledged he was to blame and asked the victim's widow, Kateryna Shelipova, to forgive him.
Addressing the World Economic Forum in Davos, Switzerland, on Monday, Ukrainian President Volodymyr Zelenskyy said 87 people were killed in a Russian attack earlier this month on a military base in a region of northern Ukraine that was earlier reclaimed by Kyiv's forces.
"Today, under the rubble in Desna, there are 87 victims. Eighty-seven corpses, victims who were killed," Mr Zelenskyy said, referring to Russian strikes on 17 May on a village that is home to a Ukrainian military base in the Chernigiv region.
