Ukraine refuses to surrender Mariupol amid Russia's humanitarian 'catastrophe' warning

Ukraine's deputy prime minister told media on Sunday that the country has rejected an ultimatum to surrender the besieged port city of Mariupol to Russian forces.

"There can be no talk of surrendering weapons. We have already informed the Russian side of this," Iryna Vereshchuk told the Ukrainska Pravda newspaper.

Moscow should not waste its time in 'eight pages on letters' and, instead, should just open the corridors, she further said.

The minister's rejection of Russia's demand came after Colonel-General Mikhail Mizintsev, the director of the Russian National Centre for Defense Management, called on Kyiv to 'let go' of the besieged town in south-eastern Ukraine.

Under Russia's proposal, civilians would be allowed to leave if the city's defenders laid down arms.

Around 300,000 people are believed to be trapped there with supplies running out and aid blocked from entering.

Mariupol, a strategic, mostly Russian-speaking port in the southeast, has been one of the main targets of Moscow's attacks. Capturing Mariupol would help Russian forces secure a land corridor to the Crimea peninsula that Moscow annexed from Ukraine in 2014.

Mariupol has suffered some of the heaviest bombardments since Russia invaded Ukraine on February 24. Many of its 400,000 residents remain trapped with little if any food, water and power.

A senior naval commander in Russia's Black Sea Fleet has been killed in Mariupol, the governor of Sevastopol said on Sunday. Post-Captain Andrei Paliy, deputy commander of the fleet, died during fighting in Mariupol, Governor Mikhail Razvozhayev said on the messaging app Telegram.

Ukraine President Volodymyr Zelensky has called for urgent talks with Moscow saying that peace talks are the "only chance for Russia to minimise the damage done with their own mistakes".

Russia says for the second day in a row it has fired its newest hypersonic missiles in Ukraine, destroying a fuel storage site in the country's south.

Zelensky urged Israel to abandon its effort to maintain neutrality following Russia's invasion, saying the time had come for the Jewish state to firmly back his country.

Ten million people -- more than a quarter of the population -- have now fled their homes in Ukraine due to Russia's "devastating" war, the United Nations refugees chief says Sunday. More than 3.3 million of them have escaped the country.