Russian drones and missiles pummelled Ukraine's struggling energy infrastructure early Friday, cutting power to thousands across the country and killing a seven-year-old boy.

The Russian barrage of hundreds of drones and nearly three dozen missiles disrupted power supplies in nine regions of Ukraine and plunged entire districts of Kyiv into darkness.

AFP journalists in the capital heard several powerful explosions overnight and experienced blackouts and water supply disruptions in quarters of the city.

President Volodymyr Zelensky said Russia's latest barrage on energy facilities was a "cynical and calculated attack", and urged allies to respond with concrete measures.

"What's needed is not window dressing but decisive action –- from the United States, Europe, and the G7 -– in deliveri

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