Ukraine's energy operator DTEK on Sunday announced "emergency power cuts" in the Kyiv region and two others in the east after authorities revealed Russia had launched a "massive" aerial attack on the energy grid.
"Emergency power cuts in Kyiv, in the Kyiv region, in the Donetsk region, in the Dnipropetrovsk region," DTEK wrote on social media platform Telegram.
Earlier, Ukraine's Energy Minister German Galushchenko said on Telegram that "a massive attack on our energy system is ongoing" and that Russian forces were "attacking electricity generation and transmission facilities throughout Ukraine".
AFP journalists heard explosions in the early morning in Kyiv and close to Sloviansk in the Donetsk region.
Russia's relentless aerial bombardment with missiles and drones has destroyed half of Ukraine's energy production capacity, President Volodymyr Zelensky has said.
Kyiv has implored its Western allies for help in rebuilding its energy grid -- a hugely expensive undertaking -- and to supply its forces with more aerial defence weapons.
With the harsh Ukrainian winter fast approaching, the country is already suffering from major energy shortfalls.