Lviv/Kyiv: Russian President Vladimir Putin said Western sanctions were akin to war on Saturday as his forces pressed on with their assault on Ukraine, where planned civilian evacuations from two besieged cities were called off.
Russia and Ukraine traded blame over the failure to provide safe passage to civilians fleeing the two bombarded cities, on the 10th day of a war that has fuelled Europe's biggest humanitarian disaster in decades.
The war, which began with Russia's invasion on February 24, has sent nearly 1.5 million refugees fleeing westward into the European Union and provoked unprecedented international sanctions on Moscow and warnings of a global recession.
The Russian defence ministry said its units had opened humanitarian corridors near the cities of Mariupol and Volnovakha, which have been encircled by its troops.
But in Mariupol, the city council said Russia was not observing the ceasefire and it asked residents to return to shelters and await further information on evacuation.
The International Committee of the Red Cross said it understood that evacuations of civilians from both Mariupol and Volnovakha would not now start on Saturday.
Russia's defence ministry accused Ukrainian "nationalists" of preventing civilians from leaving, RIA news agency reported.
The southeastern port has endured heavy bombardment, a sign of its strategic value to Moscow due to its position between Russian-backed separatist-held eastern Ukraine and the Black Sea Crimean peninsula, which Moscow seized from Ukraine in 2014.
"This night the shelling was harder and closer," a staff member from 'Doctors without Borders/Medecins sans Frontieres (MSF)' said, according to the aid agency. There was still no power, water, heating or mobile phone links and food was scarce.
The Ukrainian government had said the plan was to evacuate around 200,000 people from Mariupol and 15,000 from Volnovakha.
The Russian defence ministry said a broad offensive would continue in Ukraine, where it denies targeting civilians or invading, calling its actions a "special military operation".
Russian forces were carrying out strikes on military infrastructure and forces from separatist-held Donetsk were tightening the encirclement of Mariupol, Defence Ministry spokesman Igor Konashenkov said.
Aid agencies have warned of a humanitarian disaster across the country. The number of refugees could rise to 1.5 million by the end of the weekend from a current 1.3 million, said the head of the United Nations refugee agency.
Women and children crossed at the Medyka checkpoint in southeastern Poland in freezing conditions. A man crossing the other way yelled at the crowd that men should return to Ukraine and fight.
One woman, struggling to carry half a dozen bags, wept when the snacks she had packed for her and her young son, who was clutching a green dinosaur toy, fell to the ground. She gave the boy a bag to carry as they trudged slowly on.
Officials in Ukraine have reported thousands of dead and wounded civilians and Putin's decision to invade has drawn worldwide condemnation. The Kremlin leader said on Saturday Russia wanted Ukraine to be "demilitarised", "denazified" and that Ukraine should have neutral status.
"These sanctions that are being imposed are akin to a declaration of war but thank God it has not come to that," he said.
Earlier, Kremlin spokesman Dmitry Peskov accused the West of "economic banditry" and threatened to retaliate, without giving details.
The conflict has shaken international diplomacy over Iran's nuclear programme, one of the few areas where Russia and the United States had been working together to curb what the West suspects is an Iranian plan to develop nuclear arms.
Russian Foreign Minister Sergei Lavrov said on Saturday the new Western sanctions imposed on his country had become a stumbling block for clinching a nuclear deal with Iran.
A senior Iranian official told Reuters the Russian stance was not helpful.
'Please close the sky'
Ukraine says Russian forces have focused efforts on encircling Kyiv and Kharkiv, the second-biggest city, while aiming to establish a land bridge to Crimea.
Kyiv, in the path of a Russian armoured column that has been stalled outside the Ukrainian capital for days, was again under attack, with explosions audible from the city centre.
Ukrainian President Volodymyr Zelenskiy was expected to press Washington for more help in a video call with the US Senate at 9:30am ET (1430 GMT) on Saturday.
At a meeting on Friday, NATO allies rejected Ukraine's appeal for no-fly zones, saying they were increasing support but that stepping in directly could make the situation worse.
"Please close the sky ... because people are dying," said Solomiya Zdryko, 18, who fled from Lviv in western Ukraine.
US Secretary of State Antony Blinken, on a visit to Poland, discussed security and humanitarian assistance with top officials there. Poland has taken in the vast majority of Ukrainian refugees.
Ukraine's Defence Minister Oleksii Reznikov said 66,224 Ukrainian men had returned from abroad to join the fight against Russia's invasion. "Ukrainians, we are invincible," he said in an online post.
Ukraine's military said armed forces "are fighting fiercely to liberate Ukrainian cities from Russian occupiers", counter-attacking in some areas and disrupting communications.
"Units of the invaders are demoralized, soldiers and officers of the occupying army continue to surrender, flee, leaving weapons and equipment on Ukrainian soil," it said, adding that at least 39 Russian planes and 40 helicopters had been destroyed.
Russia said it had destroyed 82 Ukrainian aircraft, 708 armoured vehicles, 74 multiple rocket launchers and 56 drones.
Reuters has not been able to independently verify such accounts from either side.
Russian forces have made their biggest advances in the south, where they captured their first sizeable Ukrainian city, Kherson, this week.
On Saturday, a crowd marched through the streets of the city of 250,000 people, waving Ukrainian flags and shouting "Kherson is Ukrainian!" as Russian troops stood by.