UK Prime Minister Boris Johnson joined the stream of European leaders showing their support for Ukraine by travelling to the nation's capital for face-to-face meetings with President Volodymyr Zelenskyy.
Mr Johnson's surprise Saturday visit included a pledge of new military assistance, including 120 armoured vehicles and new anti-ship missile systems.
This came a day after he promised to send an additional $174 million of high-grade military equipment to Ukraine, saying Britain wanted to help Ukraine defend itself against Russian aggression.
Mr Johnson also confirmed further economic support, guaranteeing an additional $670 million in World Bank lending to Ukraine, taking Britain's total loan guarantee to up to $1.3 billion.
"Today I met my friend President @ZelenskyyUa in Kyiv as a show of our unwavering support for the people of Ukraine,'' Mr Johnson said on Twitter.
He said Britain was offering a new package of financial and military aid to help Ukraine against "Russia's barbaric campaign".
The Ukrainian leader praised the actions of the UK and encouraged other countries to follow suit.
"We must put more and more pressure on the Russian Federation, work harder to help the people of Ukraine defend it against the Russian Federation, and step up sanctions," Mr Zelenskyy said.
An image of the two leaders meeting was posted online by the Ukrainian Embassy in London with the headline: "Surprise," and a winking smiley face.
Zelenskyy seeks peace despite atrocities
Mr Zelenskyy said he was committed to pressing for peace, despite Russian attacks on civilians that have stunned the world, and he renewed his plea for more weapons ahead of an expected surge in fighting in the country's east.
He made the comments a day after at least 52 people were killed in a strike on a train station in the eastern city of Kramatorsk, and as evidence of civilian killings came to light after Russian troops failed to seize the capital, Kyiv, where Mr Zelenskyy has hunkered down.
"No one wants to negotiate with a person or people who tortured this nation. It's all understandable. And, as a man, as a father, I understand this very well," Mr Zelenskyy said.
"[But] we don't want to lose opportunities, if we have them, for a diplomatic solution.
Russian troops that withdrew from northern Ukraine are now regrouping for what is expected to be an intensified push to retake the eastern Donbas region, including the besieged port city of Mariupol that Ukrainian fighters are striving to defend.
The Ukrainian President said those defenders were tying up "a big part of the enemy forces", characterising the battle to hold Mariupol as "the heart of the war" right now.
"It's beating. We're fighting. We're strong. And, if it stops beating, we will be in a weaker position," he said.
Mr Zelenskyy said he was confident Ukrainians would accept peace, despite the horrors they have witnessed in the more-than-six-week-long war.
Those horrors have included gruesome images of bodies of civilians found in yards, parks and city squares and buried in mass graves in the Kyiv suburb of Bucha after Russian troops withdrew.
Ukrainian and Western leaders have accused Moscow of war crimes.
Russia has falsely claimed that the scenes in Bucha were staged. It also put the blame on Ukraine for the attack on the train station in Kramatorsk as thousands of people rushed to flee ahead of an expected Russian offensive.
Despite hopes for peace, Mr Zelenskyy acknowledged that he must be "realistic" about the prospects for a swift resolution, given that negotiations have so far been limited to low-level talks that do not include Russian President Vladimir Putin.
Huge convoy heading to Donbas
Newly released Maxar satellite imagery collected on Friday shows a 13 kilometre-long convoy of military vehicles headed south to the Donbas region through the Ukrainian town of Velykyi Burluk.
Velykyi Burluk is about 23kms south-west of the Russian border.
Western military analysts said an arc of territory in eastern Ukraine was under Russian control, from Kharkiv — Ukraine's second-largest city — in the north to Kherson in the south.
But counterattacks are threatening Russian control of Kherson, according to the Western assessments, and Ukrainian forces are repelling Russian assaults elsewhere in the Donbas, a largely Russian-speaking and industrial region.
NATO plans permanent military presence at border
NATO is working on plans for a permanent military presence on its border in an effort to battle future Russian aggression, The Telegraph reported, citing NATO secretary-general Jens Stoltenberg.
NATO was "in the midst of a very fundamental transformation" that would reflect "the long-term consequences" of Mr Putin's actions, Mr Stoltenberg said in an interview with the newspaper.
"Therefore, we have now asked our military commanders to provide options for what we call a reset, a longer-term adaptation of NATO."
Mr Stoltenberg, who recently said he would extend his term as head of the alliance by a year, also said in the interview that decisions on the reset would be made at a NATO summit to be held in Madrid in June.
Russia's invasion of Ukraine has triggered Europe's largest refugee crisis since World War II and led Western nations to rethink their defence policies.
Residents emerge from school basement to count the dead
The names of the dead are scrawled on the peeling wall of a school basement where residents say more than 300 people were trapped for weeks by Russian occupiers in Yahidne, a village north of the Ukrainian capital, Kyiv.
Halyna Tolochina, a member of the village council, struggled to compose herself as she went through the list, scribbled in black on the plaster on either side of a green door, in the gloomy warren where she said she and hundreds of others were confined.
To the left of the door were scrawled the seven names of people killed by Russian soldiers.
To the right were the 10 names of people who died because of the harsh conditions in the basement, she said.
"This old man died first," Tolochina said, pointing at the name of Muzyka D, for Dmytro Muzyka, whose death was recorded on March 9.
She said Mr Muzyka's body lay for a few days in a boiler room until, during a break in shelling, some people were allowed to take the dead to be buried in hastily dug graves in the village cemetery.
Reuters spoke to seven residents of Yahidne who said that, in total, at least 20 people died or were killed during the Russian occupation.
No official death toll has been released by Ukrainian authorities.
Reuters was not able to verify independently the villagers' accounts. Reporters saw one freshly dug grave in a field by the village and two bodies wrapped in white plastic sheets.
The Kremlin did not respond to requests for comment on the events in Yahidne.
UK to send anti-tank missiles and precision munitions
The package of military aid Britain announced on Friday includes more Starstreak anti-aircraft missiles, another 800 anti-tank missiles and precision munitions capable of lingering in the sky until directed to their target.
"It is because of President Zelenskyy's resolute leadership and the invincible heroism and courage of the Ukrainian people that [Russian President Vladimir] Putin's monstrous aims are being thwarted.''
Mr Johnson reiterated remarks made earlier by the head of the European Commission, Ursula von der Leyen, of the EU preparing for more sanctions against Russia.
EU raises over $13 billion for Ukraine
As Mr Zelenskyy makes a continuous round of virtual appearances to drum up support from politicians around the world, other European leaders have decided the time is right to travel to Ukraine's capital, Kyiv, for in-person talks.
Ms von der Leyen was in Kyiv on Friday, following earlier visits from the Czech, Polish, Slovenian and Austrian prime ministers.
She also travelled to the town of Bucha near Kyiv where Ukrainian authorities have begun exhuming the bodies of civilians believed to have been killed by Russian forces, in what has been described by the Ukrainian President as a "massacre".
On Saturday, Ms von der Leyen travelled to Warsaw to lead a fundraising event she said had raised 9.1 billion euros ($13.3 billion) for Ukrainian refugees.
The global pledging event, which was also launched by Canadian Prime Minister Justin Trudeau, sought to raise money for internally displaced people in Ukraine and refugees from the war-ravaged country, organisers said.
More than 4.4 million refugees have fled Ukraine since the Russian invasion began on February 24.
The event, partnered by the Global Citizen movement, comprised a social media rally on Friday and a pledging conference on Saturday.
Artists including Elton John, Alanis Morissette, Billie Eilish, Annie Lennox and Chris Rock joined the campaign alongside global leaders pledging for their countries.
In his daily late-night video address to the nation, Mr Zelenskyy thanked Ms von der Leyen and Canadian Prime Minister Justin Trudeau for the global fundraising event.
ABC/wires
