Ukrainian forces secured full control of Kharkiv on Sunday following street fighting with Russian troops in the country's second-biggest city, the local governor said.
"Kharkiv is fully under our control," the head of the regional administration, Oleg Sinegubov, said on messaging app Telegram, adding that the army was expelling Russian forces during a "clean-up" operation.
Earlier on Sunday he had said that Russian forces' light vehicles broke into the city, with fighting breaking out in the streets.
An AFP correspondent in the city heard machine gunfire and explosions.
Mr Sinegubov said that Russian troops were "absolutely demoralised".
He said Russian forces were abandoning their vehicles "in the middle of the road" and groups of five were surrendering to the Ukrainian army.
"As soon as they see at least one representative of the armed forces, they surrender," Mr Sinegubov said.
He said that "dozens" of Russian soldiers have already surrendered.
"The captured Russian fighters speak of complete exhaustion and demoralisation, they have no connection with the central command, they do not understand and do not know what they do next," the Kharkiv governor said.
"Since the beginning of the attack on Ukraine, they have not received food and water," he added.
"Leaving the positions, Russian fighters are trying to hide among the civilian population, asking people for clothes and food."
'They fight against all living things'
Ukrainian President Volodymyr Zelenskyy said Sunday that Moscow was bombarding residential areas in Ukraine as its invading forces sought to push deeper into the pro-Western country.
"The past night in Ukraine was brutal, again shooting, again bombardments of residential areas, civilian infrastructure," Mr Zelenskyy said in an address posted online.
Ukrainian President Volodymyr Zelensky speaking about the current situation in Ukraine. Source: AAP / UKRAINIAN PRESIDENTIAL PRESS SERVICE HANDOUT/EPA
He said Russian forces were "firing rockets and missiles at entire city districts in which there isn't and never has been any military infrastructure".
A big fire at a petroleum storage depot after a Russian missile attack, in Vasylkiv, near Kiev, Ukraine. Source: EPA / ALISA YAKUBOVYCH/EPA
The Russian defence ministry claimed on Sunday that its troops had besieged the southern Ukrainian city of Kherson and the city of Berdyansk in the southeast.
"Over the past 24 hours, the cities of Kherson and Berdyansk have been completely blocked by the Russian armed forces," defence ministry spokesman Igor Konashenkov said in a statement.
He added that Russian troops had also taken control of Genichesk, a port city along the Sea of Azov, and an airfield near Kherson.
As of Sunday, the Russian army said it had destroyed 975 military facilities in Ukraine and shot down eight fighter jets, seven helicopters and 11 drones.
Russian forces also attacked oil and gas facilities in Ukraine early on Sunday, sparking huge explosions. Missile struck an oil terminal in Vasylkiv, southwest of Kyiv, the town's mayor said. Blasts sent huge flames and billowing black smoke into the night sky, online posts showed.
"The enemy wants to destroy everything," said the mayor of Vasylkiv, Natalia Balasinovich.
Russian-backed separatists in the eastern province of Luhansk said a Ukrainian missile had blown an oil terminal in the town of Rovenky.
Mr Konashenkov claimed that Ukrainian servicemen were laying down arms "en masse."
He claimed that on Saturday forces of an air defence missile regiment near Kharkiv "voluntarily" put down their arms, adding that more than 470 Ukrainian servicemen had been detained.
There was no independent verification of any of these claims and Ukraine insists it has inflicted heavy casualties on the Kremlin's forces.
Russian President Vladimir Putin launched what he called a special military operation on Thursday, ignoring weeks of Western warnings and saying the "neo-Nazis" ruling Ukraine threatened Russia's security - a charge Kyiv and Western governments say is baseless propaganda.
Russian President Vladimir Putin says the "neo-Nazis" ruling Ukraine have threatened Russia's security.
Western allies prepare new sanctions
The United States and its European partners said they also would impose restrictions on Russia's central bank to limit its ability to support the rouble and finance Mr Putin's war effort.
"We are resolved to continue imposing costs on Russia that will further isolate Russia from the international financial system and our economies," said a statement from the United States, France, Germany, Canada, Italy, Britain and the European Commission.
After initially shying away from such a move largely because of concern about the impact on their economies, the allies said they committed to "ensuring that selecte
They did not name the banks that would be expelled, but an EU diplomat said some 70 per cent of the Russian banking market would be affected.
The decision - which the French finance minister had called a "financial nuclear weapon" because of the damage it would inflict on the Russian economy - deals a blow to Russia's trade and makes it harder for its companies to do business.
SWIFT, a secure messaging network that facilitates rapid cross-border payments, said it was preparing to implement the measures.
Sanctions on Russia's central bank could limit Mr Putin's use of his more than $US630 billion ($A871 billion) in international reserves, widely seen as insulating Russia from some economic harm.
Google barred Russia's state-owned media outlet RT and other channels from receiving money for ads on their websites, apps and YouTube videos, similar to move Facebook made.
The UN Office for the Coordination of Humanitarian Affairs (OCHA) estimated at least 64 civilians have been killed and more than 160,000 are on the move, but added the actual death toll was likely to be "considerably higher".
Damage to civilian infrastructure has left hundreds of thousands of people without electricity or water.
Hundreds of homes had been damaged or destroyed, while bridges and roads hit by shelling had left some communities cut off from markets, it said.
It cited the UN refugee agency as saying more than 160,000 people had been internally displaced and more than 116,000 forced to flee into neighbouring countries.
Interfax quoted Ukraine's health ministry as saying at least 198 Ukrainians, including three children, have been killed and 1,115 people wounded.
A Ukrainian presidential adviser said about 3,500 Russian soldiers had been killed or wounded. Western officials have said intelligence showed Russia suffering higher casualties than expected.
Russia has not released casualty figures and it was impossible to verify tolls or the precise picture on the ground.
Ukraine, a democratic nation of 44 million people, won independence from Moscow in 1991 after the fall of the Soviet Union and wants to join NATO and the EU, goals Russia opposes.
Mr Putin has said he must eliminate what he calls a serious threat to his country from its smaller neighbour, accusing it of genocide against Russian-speakers in eastern Ukraine - something Kyiv and its Western allies reject as a lie.
UN refugee chief Filippo Grandi said more than 150,000 Ukrainian refugees had crossed into Poland, Hungary, Moldova and Romania.
