Up to 3,000 Ukraine troops killed since Russia invaded, says Zelenskiy, as battle rages in Mariupol

Ukraine president claims up to 20,000 Russian soldiers have died; reprisals from Moscow expected in wake of sinking of flagship cruiser the Moskva

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Volodymyr Zelenskiy has said up to 3,000 Ukrainian troops have been killed since Vladimir Putin ordered the invasion of Ukraine on 24 February, with no total yet available for civilian casualties, as fighting intensified in the battle for the southern city of Mariupol.

Ukraine's president said the military situation in the south and east was still very difficult", while praising the work of his armed forces. The successes of our military on the battlefield are really significant, historically significant. But they are still not enough to clean our land of the occupiers," he said in a late-night video address, calling again for allies to send heavier weapons and for an international embargo on Russian oil.