Live updates: follow the latest news on Russia-Ukraine
Cities across Ukraine came under renewed shelling and bombardment as a mosque in the port city of Mariupol, which was sheltering 80 civilians, was shelled by Russian forces, Ukraine's foreign ministry said on Saturday.
"The mosque of Sultan Suleiman the Magnificent and his wife Roxolana (Hurrem Sultan) in Mariupol was shelled by Russian invaders," the ministry wrote on its Twitter account.
"More than 80 adults and children are hiding there from the shelling, including citizens of Turkey."
Russian forces began slowly surrounding Kyiv on Saturday as fighting raged near the capital city.
The bulk of Russian ground forces took positions about 25 kilometres from the centre of the Ukrainian capital, Britain's defence ministry said. Several other cities were also surrounded and faced heavy shelling.
It was hoped that civilians trapped in Ukrainian cities would be able to escape on Saturday, said Ukraine's Deputy Prime Minister Iryna Vereshchuk.
She said she hoped that several humanitarian corridors would open for thousands of residents in the bombarded cities, including from the besieged port city of Mariupol to Zaporizhzhia.
"I hope that the day will go well, all the planned routes will be open and Russia will fulfil its obligations to guarantee the ceasefire regime," Ms Vereshchuk said in a video address after repeated evacuation efforts this week failed.
Air raid sirens sounded across most Ukrainian cities on Saturday morning, urging people to seek shelter, local media reported.
The UK defence ministry said on Saturday that fighting north-west of the capital continued and the cities of Kharkiv, Chernihiv, Sumy and Mariupol remained encircled under heavy Russian shelling.
At least 1,582 civilians in the south-eastern city of Mariupol have been killed as a result of Russian shelling and a 12-day blockade, the city council said in an online statement on Friday. It was not possible to verify casualty figures, according to Reuters.
Efforts to isolate Russia economically have intensified, with the US imposing new sanctions on senior Kremlin officials and Russian oligarchs and the EU set to strip Russia of its privileged trade status on Saturday.
A superyacht owned by Russian billionaire Andrey Igorevich Melnichenko was seized by Italian police.
The $578 million Sailing Yacht A – which is the world’s biggest sailing yacht, according to the Italian government – has been sequestered at the northern port of Trieste, the government said.
The seizure was confirmed by the prime minister's office on Saturday, a few days after the businessman was placed on EU sanctions.
Mr Melnichenko is one of many wealthy Russians who have been penalised by Western states for their links to Russian President Vladimir Putin.
With the Russian assault in its third week, Mr Zelenskiyy, who has rallied his people with a series of addresses from the capital Kyiv, said Ukraine had "already reached a strategic turning point".
"It is impossible to say how many days we still have (ahead of us) to free Ukrainian land. But we can say we will do it," he said. "We are already moving towards our goal, our victory."
Russian forces had kept up their bombardment of cities across the country on Friday in the biggest assault on a European country since the Second World War.
The fighting has created more than two million refugees, and thousands of Ukrainians are trapped in besieged cities.
