Russia readies for southern offensive as alarm raised over shelling of nuclear plant

UN watchdog raises concerns as Russia and Ukraine trade blame for attack on Europe's largest nuclear power station

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Russia is strengthening its positions and numbers on Ukraine's southern front to ready itself for a Ukrainian counteroffensive and is likely to be preparing the ground to attack, according to British and Ukrainian military authorities.

The assessment came as both sides traded blame for renewed shelling on Europe's largest nuclear plant, with the UN nuclear watchdog raising grave concerns about the attack.