Zelensky also says he remains confident of continued US and European financial aid despite 'political storms' in Washington and elsewhere.

Helicopter pilots must fly at low altitudes to avoid becoming targets for enemy anti-aircraft defences.

Russian forces do not control any of the regions in full.

Russia denies committing atrocities or targeting civilians in Ukraine.

A major cyberattack also interrupted internet services on the peninsula, Russian-installed officials say.

Moscow says Ukraine is using the case as a roundabout way to get a ruling on the overall legality of its military action.

Putin has said Ukraine's counteroffensive against Russian forces had so far failed and that the Ukrainian army had sustained heavy losses.

Ukraine has been making efforts to allow vessels stranded in Odesa port since the start of the Russia-Ukraine conflict to sail into open waters after the collapse of the UN-backed Black Sea grains corridor.

The mobilisation campaign could target between 400,000 and 700,000 recruits, reports say.

With Moscow's stretched military resources and dissent in the ranks, both sides have measured recent successes by taking control of tiny villages or small pockets of land.

Kyiv has retaken a number of villages and settlements in its three-month-old offensive but its soldiers have been hampered by vast Russian minefields and trenches.

Moscow has said very little so far about the Kinzhal air-launched ballistic missile, but Ukraine's military Kyiv says Russia uses them frequently.