Russia-Ukraine war: Boris Johnson visits Kyiv as Zelenskiy warns Russia over ‘nuclear blackmail’ – as it happened

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The UN has said it is very concerned" about plans by Russian-backed authorities to hold trials for captured Ukrainian soldiers in Mariupol.

Pro-Russian officials appear to be installing metal cages in a hall in Mariupol as part of plans to establish what they were calling an international tribunal", a UN rights office spokesperson said, adding that such a process could itself amount to a war crime.