Vladimir Putin accused of war crimes as school and theatre are hit in Ukraine

Russia has been accused by the UK, the US, France, Albania, Ireland and Norway of war crimes in Ukraine, as Paris claimed Vladimir Putin was only pretending to be interested in negotiating a peace deal.

The six countries challenged Russia before a UN security council meeting as the British foreign secretary, Liz Truss, said there was now “very, very strong evidence” of war crimes being committed by Russian forces.

“Vladimir Putin is behind them,” Truss said. “It is ultimately a matter for the international criminal court to decide who is or isn’t a war criminal and for us to bring the evidence.”

The US secretary of state, Antony Blinken, said he agreed with Joe Biden that war crimes had been committed in Ukraine, adding that US experts were in the process of documenting and evaluating potential war crimes.

The World Health Organization director-general, Tedros Adhanom Ghebreyesus, told the UN security council that they had verified 43 attacks on health care facilities in Ukraine that have killed 12 people and injured dozens more without specifying who was behind it. “In any conflict, attacks on health care are a violation of international humanitarian law,” he said.

The UN’s undersecretary-general Rosemary DiCarlo called for an investigation into the reported attacks on civilians.

She told the meeting that “international humanitarian law is crystal clear” and the attacks “are reportedly indiscriminate, resulting in civilian casualties and damage to civilian infrastructure.”

Earlier, Blinken, who has repeatedly warned that Putin will turn to the use of chemical weapons, said the US administration was gathering evidence of war crimes and appeared to dismiss hopes of a resolution through diplomacy.

He said: “The actions that we’re seeing Russia take every single day, virtually every minute of every day, are in total contrast to any serious diplomatic effort to end the war.”

On Thursday night, British defence intelligence analysts said they believed Russia was being forced to divert “large numbers” of troops to defend its supply lines rather than continuing its attacks in Ukraine.

The latest intelligence assessment published by the Ministry of Defence said logistical problems “continue to beset Russia’s faltering invasion”.

Rescue workers continued to search through the rubble for survivors of a Russian airstrike on a theatre in the besieged Ukrainian city of Mariupol where hundreds of people had been sheltering.

Officials said more than 20 people were killed and 25 injured in an airstrike on a school and community centre in Merefa, close to the north-eastern city of Kharkiv, in the early hours of Thursday morning.

Oleksii Reznikov, Ukraine’s defence minister, described the pilot who bombed the theatre in Mariupol as a monster. The word “children” had been painted in large Russian script on the ground outside the red-roofed theatre building to warn off fighter jets.

Speaking via video link to a committee of MEPs, Reznikov, who has been leading the Ukrainian delegation in peace talks with Russia, said the first step to any deal was an immediate ceasefire but he feared the Kremlin would first need to be defeated in battle.

“We will of course first of all during the negotiations talk about a ceasefire, about humanitarian corridors, the provision of the civilian population with evacuation, with water, with food, and maybe later we can sign this agreement for peace,” he said.

“But on the terms of Ukrainian people – we would never accept any capitulation and our armed forces are ready to resist. So today we could say the negotiations are more or less on a technical level. And of course lawyers are involved, politicians are involved, and I’m not going to go into more details about negotiations.”

He added: “I have to assure you that there is nothing yet to be satisfied about. But I hope that we will end this war very soon and of course by defeating the Kremlin.”

Reznikov told MEPs that international leaders such as Israel’s prime minister, Naftali Bennett, had been trying to mediate. However, there are major doubts within the Ukrainian negotiating team and in western capitals about whether Putin is prepared to choose peace.

France’s foreign minister, Jean-Yves Le Drian, said he believed the Russian president was pretending to negotiate as part of a battle plan also used in Chechnya and Syria.

“Unfortunately, we’re still facing the same Russian logic – making maximalist demands, wanting Ukraine to surrender and intensifying siege warfare,” Le Drian told Le Parisien newspaper. “Just as in Grozny [in Chechnya] and Aleppo [in Syria], there are three typical elements – indiscriminate bombardment, so-called humanitarian corridors designed to allow them to accuse the other side of failing to respect them, and talks with no objective other than pretending that they are negotiating.”

Le Drian said there was only one way for Putin to show he was interested in peace and that was by engaging with “one urgent matter – ceasefire, ceasefire, ceasefire”.

“Russia refuses that for now,” he said. “So the sanctions will be intensified in a determined way until Putin realises that the price for continuing the conflict will be so high that a ceasefire is preferable and starts real talks with President Zelenskiy.”

The Kremlin on Thursday said Russia was putting “colossal” energy into talks but did not see such “zeal” from Kyiv.

One western official said that while the Russian negotiators appeared to be serious about their task, Putin’s television appearance on Wednesday should be a cause for doubt. The Russian president spoke of a western plot to destroy Russia and described his domestic opponents as “traitors and scum”.

“The question of whether Russia is prepared to compromise on its demands is a very big question,” the official said. “Those of you who saw President Putin addressing the nation yesterday would be forgiven for thinking that Russia was not in compromising mood.

“And in the end a lot of this is going to come down to what Putin wants … Negotiations are serious and are worth pursuing. But as he says, where and whether they will end up somewhere useful I think is still very unknown.”

Russia has been demanding that Ukraine become a “neutral state” and abandon its aspirations to join Nato. The Kremlin also wants Kyiv to accept the loss of Crimea, which Moscow illegally annexed in 2014, and the self-proclaimed republics in Donetsk and Luhansk.

Slovenia’s prime minister, Janez Janša, who saw Volodymyr Zelenskiy in Kyiv on Tuesday evening, told the Guardian that the Ukrainian president was open to changing the constitution to satisfy Russia’s demand on Nato but that Ukraine wanted iron-clad guarantees from world powers that they would intervene in any future conflict provoked by the Kremlin.

“If we want a real peace agreement, something which will last many generations, I don’t think that this is possible only to negotiate between Russia and Ukraine,” he said. “I think that at the same table, as guarantors, there should be United States, European Union and China.”

The US president, Joe Biden, is to hold a call on Friday with the Chinese leader, Xi Jinping. There were seven hours of talks on Monday in Rome between the White House national security adviser, Jake Sullivan, and his Chinese counterpart, Yang Jiechi.