VLADIMIR Putin’s forces are committing war crimes as Russian troops step up the bombardment of Ukraine’s cities, Boris Johnson has said.

The Prime Minister accused the Russian president of “abhorrent” attacks as Ukraine’s capital Kyiv braced for a siege and second city Kharkiv suffered a further pounding.

Johnson spoke to Ukraine’s President Volodymyr Zelenskyy on Wednesday morning, promising further support and weapons for the forces resisting Russia’s military.

Strikes that damaged the Babi Yar Holocaust memorial in Kyiv and the central square in Kharkiv have caused revulsion, and Western allies fear it is a sign of a shift in Russian tactics further towards the indiscriminate targeting of urban areas.

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For the first time the UK explicitly accused Putin of war crimes, with Downing Street claiming “horrific acts” were occurring on an almost hourly basis as population centres are targeted.

At Prime Minister’s Questions, Johnson said: “Putin has gravely miscalculated. In his abhorrent assault on a sovereign nation, he has underestimated the extraordinary fortitude of the Ukrainian people and the unity and resolve of the free world in standing up to his barbarism.”

More than 2000 civilians have died since the invasion, Ukraine’s state emergency service said, although that figure has not been independently verified.

The United Nations’ refugee agency believes around 874,000 people have fled Ukraine but that figure is soon expected to reach a million.

Johnson told MPs: “What we have seen already from Vladimir Putin’s regime in the use of the munitions that they have already been dropping on innocent civilians, in my view, already fully qualifies as a war crime.”

But the Prime Minister said “the vice is tightening on the Putin regime” through the sanctions imposed by the West.

He promised to publish a list of people associated with Putin who could be liable for sanctions.

But he was urged by Labour leader Keir Starmer to immediately ramp up the measures against allies of the Russian leader.

Starmer, who called for Chelsea owner Roman Abramovich (below) to face sanctions, said: “Now is the time to sanction every oligarch and crack open every shell company so we can prove Putin wrong.”

The Russian-Israeli billionaire later announced he will sell the club, with the “net proceeds” going to a charity supporting victims of the war in Ukraine.

The National: The trustees of the Chelsea Foundation made a serious incident report to the Charity Commission after Roman Abramovich, pictured, said he was handing stewardship of the club to them

UK officials have said more sanctions are coming, against oligarchs, Russian National Security Council members and banks, and that they believe the economic shock of the moves has been more significant than Mr Putin was expecting.

They said they wanted sanctions to go further, including the banning from the Swift payment system to apply to all Russian banks.

In other developments:

  • Johnson announced the Government would match donations to the Disasters Emergency Committee’s Ukraine appeal, starting with £20 million.
  • The European Union announced that seven Russian banks were being excluded from the Swift system which allows fast and efficient interbank transactions.
  • The UN General Assembly voted overwhelmingly to demand that Russia immediately stops using force against Ukraine and withdraws its military from the country, with 141 nations backing the motion and only five, including alleged co-aggressor Belarus, opposing it.
  • Russia said it would be ready for further peace talks with Ukraine later on Wednesday.
  • Ukrainian ambassador to the UK Vadym Prystaiko was given a standing ovation by MPs in the Commons.

The lack of progress in meeting the aims of the invasion had led to a change in tactics, focusing on aerial and artillery bombardment of cities rather than the kind of lightning military advances originally envisaged by the Kremlin, Western analysts believe.

Defence Secretary Ben Wallace said Russian forces will seek to “pummel” Ukraine’s cities in tactics reminiscent of medieval siege warfare.

A strike hit the regional police and intelligence headquarters in Kharkiv, killing four people and wounding several, with residential buildings also hit according to the Ukrainian authorities.

The Ukrainian Unian news agency reported that two cruise missiles hit a hospital in Chernihiv, north Ukraine.

The National: Ben Wallace

Wallace (above) said the advance of Russian forces continued to be slowed by a combination of overstretched logistics, poor morale and brave resistance by Ukrainian fighters.

There was “low morale in the Russian forces, we’ve seen lots of surrenders”.

However, he told the BBC: “That doesn’t take away from the fact you have a very ruthless Russian armed forces leadership and a president who seems to know no limit to how much violence they will use to achieve their aims.”

The use of overwhelming firepower against cities had been used in Chechnya but Ukraine is a different proposition because of its size and population.

Wallace warned that an occupying force would face the kind of insurgency faced by the Soviets in Afghanistan or the UK and allies in Iraq.

There could be “years of resistance” to a Russian occupation, he said.

The Defence Secretary again rejected calls for the UK and its allies to enforce a no-fly zone in the skies above Ukraine, because shooting down a Russian plane could trigger a Europe-wide conflict between Putin and Nato.

A no-fly zone would also have to apply to Ukrainian jets, meaning they could not target Russian forces from the air, he added.

But he said the UK had “led the way” in supplying surface-to-air weapons systems to Ukraine.

The risk of a Nato-Russia clash was underlined by Russian foreign minister Sergei Lavrov, who warned “a third world war will be nuclear, and devastating”.