In a joint statement, the foreign ministers of the Group of Seven called on Russia to comply with the International Court of Justice’s order to stop its attack and withdraw its forces.

While the UN’s political chief called for an investigation of massive civilian casualties and the destruction of hundreds of residential buildings, schools, hospitals and other civilian infrastructure in Ukraine, and for those responsible to be held accountable.

Undersecretary-General Rosemary DiCarlo told the UN Security Council on Thursday that “international humanitarian law is crystal clear” in prohibiting direct attacks on civilians in military operations and ensuring their protection.

Yet, she said, many of the daily attacks that are battering Ukrainian cities “are reportedly indiscriminate, resulting in civilian casualties and damage to civilian infrastructure.”

It came as there were further reports of civilian deaths as Russian forces continued to pound cities across Ukraine.

In the northern city of Chernihiv, at least 53 people had been brought to morgues over the past 24 hours, killed amid heavy Russian air attacks and ground fire, the local governor, Viacheslav Chaus, told Ukrainian TV on Thursday.

Ukraine’s emergency services said a mother, a father and three of their children, including three-year-old twins, were killed when a Chernihiv hostel was shelled.

At least 21 people were killed when Russian artillery destroyed a school and a community centre in Merefa, near the north-east city of Kharkiv, according to mayor Veniamin Sitov.

While in eastern Ukraine, a municipal pool complex where pregnant women and women with children were taking shelter was also hit on Wednesday, according to Pavlo Kyrylenko, head of the Donetsk regional administration.

Rescuers continued to search for survivors in the ruins of a theatre in Mariupol where hundreds of people were reported to be sheltering after it was ripped apart by a Russian air strike in Mariupol.

Prior to Wednesday’s attack, up to 1,000 men, women and children were thought to have taken shelter in the Drama Theatre’s basement seeking safety from the onslaught by Mr Putin’s forces.

Earlier this week, a satellite image of the building showed the Russian word for “children” written in giant letters at both ends of the building, in an apparent bid to protect it from the shelling.

In Kyiv, where residents have been huddling in homes and shelters, emergency authorities said a fire broke out in an apartment building hit by remnants of a downed Russian rocket, killing one person.

Firefighters evacuated 30 people from the top floors of the 16-storey building and put out the blaze.

Despite the sustained bombardment of cities Vladimir Putin’s invasion of Ukraine has “largely stalled on all fronts,” British defence chiefs said on Thursday.

They stressed that Russian forces were making “minimal progress” on land sea or air and were continuing to “suffer heavy losses”.

As the conflict entered its fourth week, they also stressed that Mr Putin’s troops had failed to seize any major cities despite the heavy bombardment of Mariupol, Kharkiv and other cities which has destroyed whole districts, according to footage and reports.

An American man was killed in a Russian attack in Chernihiv, where he was seeking medical treatment for his partner. The death of Jim Hill, of Diggs, Idaho, was reported by his sister.

Ukrainian President Volodymyr Zelensky called for more help for his country in a video address to German legislators, saying thousands of people have been killed, including 108 children.

He also referred to the dire situation in Mariupol, saying: “Everything is a target for them.”

People cross the border from Ukraine into Medyka this week (Victoria Jones/PA) (PA Wire)© Provided by Evening Standard People cross the border from Ukraine into Medyka this week (Victoria Jones/PA) (PA Wire)World Health Organization Director-General Tedros Adhanom Ghebreyesus told the UN Security Council on Thursday that WHO has verified 43 attacks on hospitals and health facilities with 12 people killed and 34 injured.

In a virtual briefing, Tedros said “the disruption to services and supplies is posing an extreme risk to people with cardiovascular disease, cancer, diabetes, HIV and TB, which are among the leading causes of mortality in Ukraine.”

The WHO chief said displacement and overcrowding caused by people fleeing fighting are likely to increase the risks of diseases such as Covid, measles, pneumonia and polio.

One day after US President Joe Biden called Putin a “war criminal,” U.S. Secretary of State Antony Blinken said American officials were evaluating and documenting potential war crimes committed by Russia in Ukraine.

Mr Blinken said the intentional targeting of civilians would amount to a war crime and that there will be “massive consequences” for any such crimes that are confirmed.

Both Ukraine and Russia this week reported some progress in negotiations over a possible ceasefire.

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