A Russian deputy commander says Russia plans to take full control of Donbas and southern Ukraine as part of the second phase of its military operation.

Rustam Minnekayev, the deputy commander of Russia's central military district, was also cited by the Interfax news agency as saying Russia planned to forge a land corridor between Crimea, the Black Sea peninsula which Russia annexed in 2014, and Donbas in eastern Ukraine.

He said taking control of southern Ukraine would improve Russian access to Moldova's pro-Russian breakaway region of Transnistria, which borders Ukraine and which Kyiv fears could be used as a launching pad for new attacks against it.

"Control over the south of Ukraine is another way to Transnistria, where there is also evidence that the Russian-speaking population is being oppressed," TASS quoted Major-General Minnekayev as saying at a meeting in Russia's central Sverdlovsk region.

He was not quoted as providing any evidence to back up the claim.

Civilians 'buried in mass graves outside Mariupol'

The United Nations' human rights office on Friday pointed to what it said is growing evidence of war crimes committed by Russian forces, declaring that humanitarian law appears to have been "tossed aside".

Michelle Bachelet, the UN high commissioner for human rights, said that, "our work to date has detailed a horror story of violations perpetrated against civilians".

Her office's mission in Ukraine so far has verified 5,264 civilian casualties, including 2,345 deaths, since the war began.

It said that 92.3 per cent of those were recorded in Ukrainian government-controlled territory.

The office uses strict methodology and has long acknowledged that its confirmed figures are far short of the real numbers.

"The actual numbers are going to be much higher" as more details emerge from places such as Mariupol where there is intense fighting, Ms Bachelet said.

In Mariupol, Ukrainian fighters are still clinging to their last redoubt inside the Azovstal steelworks.

The strategic port city has been under attack since the beginning of the Russian invasion in February.

An aide to Mr Zelenskyy's chief of staff told national television that 42 villages were "added to the list of those that have been occupied" in the Donetsk region.

On Thursday, Russian President Vladimir Putin claimed victory in Mariupol despite Ukrainian forces still holding parts of the Azovstal complex.

New satellite images appeared to show over 200 new graves at a cemetery in the Ukrainian town of Manhush near Mariupol.

The imagery showed what looked like long rows of graves stretching away from an existing cemetery in the town.

Mariupol Mayor Vadym Boychenko said Russian troops were burying Ukrainian civilians to cover up "military crimes" and said hundreds of civilians had been buried in trenches near Manhush.

Ukrainian authorities estimate more than 21,000 civilians have been killed in Mariupol since Russia began its attack.

Mr Boychenko appealed on Friday for the "full evacuation" of the Ukrainian city.

"We need only one thing — the full evacuation of the population. About 100,000 people remain in Mariupol," he said on national television.

In Zaporizhzhia, where 79 Mariupol residents arrived in the first convoy of buses permitted by Russia to leave for other parts of Ukraine, Valentyna Andrushenko held back tears as she recalled the ordeal under siege.

Kyiv said no new evacuations were planned for Friday.

Moscow says it has taken 140,000 Mariupol residents to Russia; Kyiv says many of those were deported by force in what would be a war crime.

Zelenskyy says Ukraine will need billions of dollars to rebuild

Ukraine will need hundreds of billions of dollars to rebuild the country and recover from the war with Russia, President Volodymyr Zelenskyy said.

The President's assessment came as Ukrainian forces facing a new Russian offensive in the country's east lost ground, with more than 40 villages falling to the invaders.

"As of now given the economic downturn and broken economic ties, we need up to $US7 billion in financial support each month to make up for economic losses," Mr Zelenskyy said.

He was addressing a meeting of the World Bank and the International Monetary Fund (IMF) live from Ukraine.

'Exclude Russia from World Bank and IMF'

The 44-year-old leader called upon the leaders gathered in Washington for the meeting to exclude Russia from the institutions "immediately," saying bodies such as the World Bank, IMF and others were "definitely not the place for a country which is trying to ruin the lives of its neighbours".

World Bank president David Malpass applauded Mr Zelenskyy for demonstrating "powerful leadership" throughout the war.

"Mr President, you and your nation have shown strength, tenacity and heroism in the face of aggression. President Zelenskyy, the floor is yours," Mr Malpass said as he invited Mr Zelenskyy to address the gathering.

The latest military aid from the United States, announced on Thursday by US President Joe Biden, includes heavy artillery, ammunition and drones for the escalating battle in the Donbas region of eastern Ukraine.

Australian ban on Putin's daughters

The Australian government slapped travel bans and sanctions on more than 140 Russian politicians, as well as Mr Putin's daughters.

The latest round of sanctions follow similar measures from the United States and the United Kingdom.

Maria Vladimirovna Vorontsova, 36, and Katerina Vladimirovna Tikhonova, 35, are largely shielded from the public eye and it has never been publicly confirmed that Mr Putin is actually their father.

The daughter of Russian Foreign Minister Sergei Lavrov, Ekaterina Sergeevna Vinokurova, 39, has also been targeted.

Western nations have levelled sanctions against many people connected to the President and his inner sanctum, in a bid to freeze their assets around the world.

ABC/wires