UKRAINIAN President Volodymyr Zelenskyy will address a United Nations Security Council meeting convened by the UK amid growing outrage over Russian atrocities.

The UK, which currently holds the council’s presidency, said it wants to discuss the “mounting evidence of war crimes” on Tuesday and will push to ensure “justice is done”.

Evidence that appears to show Vladimir Putin’s soldiers deliberately killing civilians has been emerging as he withdraws his struggling troops from around the capital Kyiv, including from the city of Bucha.

High-resolution satellite imagery has shown bodies have been lying in the open for weeks in the Ukrainian city of Bucha, as Russia denied it had committed war crimes.

Zelenskyy has warned that worse evidence of mass killings of civilians by Moscow will emerge as the Russian president repositions his troops to the south-east.

It will be his first address to the Security Council, with members including Russia and China, and comes a day after he visited Bucha to witness the fall-out.

The Ukrainian leader accused Moscow of committing “real genocide”, as he appeared visibly emotional, flanked by his soldiers and wearing a bullet-proof vest.

Russia’s UN ambassador, Vassily Nebenzia, insisted at a news conference that during the time that Bucha was under Russian control “not a single local person has suffered from any violent action”.

But satellite imagery from commercial provider Maxar Technologies, first reported by The New York Times, proved the bodies had been there for weeks.

Western and Ukrainian leaders have accused Russia of war crimes before, and the International Criminal Court’s prosecutor has already opened an investigation. But the latest reports ratcheted up the condemnation.

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Ihor Zhovkva, deputy head of the office of the President of Ukraine, said Zelenskyy “will give all the evidence” to the international community at the Security Council meeting.

“If these awful atrocities will not change the agenda of all the world, what will change?” the adviser asked on BBC Radio 4’s Today programme.

Zhovkva said Ukraine needs “additional weapons”, including tanks and missiles, to “liberate more cities” from Russia control.

Dame Barbara Woodward, Britain’s UN ambassador, called images coming from Bucha “harrowing, appalling, probable evidence of war crimes and possibly a genocide”.

She cited hundreds of bodies being dumped in the streets or in mass graves and allegations of rape.

Also on Tuesday, Foreign Secretary Liz Truss will hold talks with her Polish counterpart, Zbigniew Rau, during the second day of her visit to the capital, Warsaw.

The National: Foreign Secretary Liz Truss

She has called for Russia to be hit with the “maximum level” of sanctions and for more weapons to be supplied to Zelenskyy’s forces to help repel the Kremlin’s troops.

“The idea that we should wait for something else bad to happen is just completely wrong,” she said, applying pressure to allies.

“The reality is that money is still flowing from the West into Putin’s war machine – and that has to stop.”

She pressed for a “clear timetable” to eliminate imports of Russian oil, gas and gold, and for a further crackdown on industries financing Moscow’s invasion.

Poland’s prime minister Mateusz Morawiecki has criticised German Chancellor Olaf Scholz for focusing on the “voices of German businesses” rather than the innocents slain in Ukraine.

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Prime Minister Boris Johnson is likely to urge Germany to set a date for phasing out Russian gas when he meets Scholz in Downing Street on Friday.

US president Joe Biden called for a war crimes trial against Russian leader Vladimir Putin and said he will seek more sanctions after the reported atrocities in Ukraine.

“You saw what happened in Bucha,” Biden said, describing Mr Putin as a “war criminal”.

German foreign minister Annalena Baerbock said photographs from Bucha show the “unbelievable brutality of the Russian leadership and those who follow its propaganda”.

French president Emmanuel Macron said there is “clear evidence of war crimes” in Bucha that demand new punitive measures.

“I’m in favour of a new round of sanctions and in particular on coal and gasoline. We need to act,” Macron said on France-Inter radio.

Though united in outrage, the European allies appeared split on how to respond.

While Poland urged Europe to quickly wean itself off Russian energy, Germany said it would stick with a gradual approach of phasing out coal and oil imports over the next few months.

Russia had withdrawn many of its forces from the capital area after being thwarted in its bid to swiftly capture Kyiv.

It has instead poured troops and mercenaries into the country’s east in a stepped-up bid to gain control of the Donbas, the largely Russian-speaking industrial region that includes the besieged southern port city of Mariupol, which has seen some of the heaviest fighting and worst suffering of the war.

About two-thirds of the Russian troops around Kyiv have left and are either in Belarus or on their way there, probably getting more supplies and reinforcements, said a senior US defence official.