Japan and Australia on Friday slapped fresh sanctions on Russian entities as punishment for Moscow's invasion of Ukraine, which the West says has been stalled by staunch resistance but continues to take a devastating toll on civilians.

Ukraine's capital Kyiv reported "chaotic" Russian shelling while rescuers in the besieged port of Mariupol dug survivors from the rubble of bombed buildings. Officials from the two countries met again for peace talks on Thursday but said their positions remained far apart.

Western sources and Ukrainian officials said Russia's assault has faltered since its troops invaded on Feb. 24, further dashing Moscow's expectations of a swift victory and the removal of President Volodymyr Zelenskiy's government.

Despite battleground setbacks and punitive sanctions by the West, Russian President Vladimir Putin has shown little sign of relenting.

His government says it is counting on China to help Russia withstand blows to its economy.

The United States, which this week announced $800 million in new military aid to Kyiv, is concerned Beijing is "considering directly assisting Russia with military equipment to use in Ukraine," Secretary of State Antony Blinken said.

President Joe Biden, who described Putin as a "murderous dictator", will make clear to China's President Xi Jinping in a call Friday that Beijing "will bear responsibility for any actions it takes to support Russia's aggression," Blinken told reporters.

The pair are due to speak at 9 a.m. Eastern time (1300 GMT), the White House said.

China has refused to condemn Russia's action in Ukraine or call it an invasion. It says it recognises Ukraine's sovereignty but that Russia has legitimate security concerns that should be addressed.

A Chinese foreign ministry official met this week with Russia's ambassador to China to exchange views on counter-terrorism and security cooperation, the Chinese foreign ministry said in a statement on Friday.

SIDES FAR APART

Tokyo and Canberra announced separate measures sanctioning Russian individuals and organisations including the state-owned arms exporter, the finance ministry and the central bank.

The war has settled into a grinding pattern of sieges of cities, with Ukrainian officials reporting Russian attacks on schools, hospitals and cultural facilities.

The United Nations human rights office in Geneva said it had recorded 2,032 civilian casualties so far in Ukraine - 780 killed and 1,252 injured.

Some 3.2 million civilians have now fled to neighbouring countries, the United Nations said.

A fourth straight day of talks between Russian and Ukrainian negotiators took place on Thursday by videolink, but the Kremlin said an agreement had yet to be reached.

Kyiv and its Western allies say Russia launched the war to subjugate a neighbour Putin calls an artificial state. Moscow says it is carrying out a "special operation" to disarm Ukraine.

DIGGING FOR SURVIVORS

Rescuers in Mariupol, a southern port city, dug survivors from the rubble of a theatre that officials said had been hit by an air strike on Wednesday as civilians took shelter there from bombardments. Russia denies striking the theatre.

Mariupol has suffered the worst humanitarian catastrophe of the war, with hundreds of thousands of civilians trapped in basements with no food, water or power. City officials say they are still not able to estimate the number of casualties from the theatre.

"Yesterday and today, despite continuous shelling, rubble is being cleared as much as is possible and people are being rescued. Information about victims is still being clarified," the city council said in a statement.

Russian Foreign Ministry spokesperson Maria Zakharova said the allegation Russia had bombed the theatre was a lie.

Northeastern and northwestern suburbs of Kyiv have suffered heavy damage but the capital itself has held firm, under a curfew and subjected to deadly rocket attacks nightly.

A building in Kyiv's Darnytsky district was extensively damaged on Thursday. As residents cleared glass, a man knelt weeping by the body of a woman covered in a bloody sheet.

Ukrainian Defence Ministry spokesperson Oleksandr Motuzyanyk said Russian forces had made no significant advances around Kyiv in the past 24-48 hours and had resorted to "chaotic" shelling.

"The Ukrainian armed forces are making every effort to stop the enemy attacking from that area," he told a press briefing in Kyiv.

British military intelligence said on Thursday Russia's invasion has largely stalled on all fronts, suffering heavy losses and making minimal progress on land, sea or air.

Viacheslav Chaus, governor of the region centred on the frontline northern city of Chernihiv, on Thursday said 53 civilians had been killed there in the past 24 hours. The toll could not be independently verified.

One of those killed in Chernihiv was a U.S. citizen, Jimmy Hill, who was gunned down while waiting in a bread line, his family said.

"His body was found in the street," his sister wrote on Facebook.