Boris Johnson has accused Vladimir Putin of unleashing “barbaric and indiscriminate” violence against Ukrainian civilians as Russian forces closed in on Kyiv.
A military convoy around 40 miles long is north of the Ukrainian capital and there are fears that the city will face a barrage of rockets and shells which could inflict devastating civilian casualties.
Speaking during a visit to Warsaw, Mr Johnson said the Russian president had decided to “bomb tower blocks, to send missiles into tower blocks, to kill children, as we are seeing in increasing numbers”.
But he said that in the “grim war” Mr Putin had “fatally underestimated” the resistance of the Ukrainians and the resolve of the West to act.
“I think he has inspired and mobilised not only his own people, he is inspiring and mobilising the world in outrage at what is happening in Ukraine,” Mr Johnson added.
UK Deputy Prime Minister Dominic Raab, a former Foreign Office lawyer, said it must be clear “both to Putin but also to commanders in Moscow and on the ground in Ukraine that they will be held accountable for any violations of the laws of war”.
He told Sky News: “Those that engage in war crimes will be held to account.”
Mr Raab told BBC Radio 4’s Today programme: “We can expect, for every stutter and stumble, him to try and come back for even more heavy-handed tactics, but that is a sign that the initial phase at least – and this is going to be a long haul – has not lived up to his expectations.”
The latest intelligence from the Ministry of Defence said the advance on Kyiv had made little progress over the past 24 hours, probably due to logistical problems.
But there had been increased use of artillery north of the capital.
Satellite images from the Maxar company showed the extent of the Russian forces massing around Kyiv, with a column of armoured vehicles, tanks, artillery and support vehicles stretching 40 miles.
Mr Johnson is visiting Poland and Estonia to help show the UK’s support for its eastern Nato allies.
Foreign Secretary Liz Truss was in Geneva addressing the United Nations Human Rights Council, where she was due to accuse Mr Putin of “violating international law”.
“He is violating human rights on an industrial scale and the world will not stand for it,” she will say.
The Prime Minister told his Polish counterpart Mateusz Morawiecki: “We stand ready, clearly, to take Ukrainian refugees in our own country, working with you, in considerable numbers, as we always have done and always will.”
But shadow home secretary Yvette Cooper told BBC Radio 4’s Today programme: “At the moment, what the Home Office is doing is trying to just tweak the existing system.
“They’re trying to carry on with a version of business as usual, with a version of asking people to apply for traditional work visas or traditional visitor visas or traditional family visas that are still narrowly drawn.
“And the normal system just doesn’t work when you are facing war in Europe, when you’re facing a crisis on this scale.”
