Ukraine's southern port city of Odesa and the surrounding region suffered major blackouts Saturday after a large overnight Russian attack on the power grid that left more than a million households without power.

President Volodymyr Zelenskyy said Russia had attacked Ukraine with more than 450 drones and 30 missiles.

"The brunt of the attack was on our energy system, on the south and Odesa region," Zelenskyy wrote on Telegram, adding that thousands of families in seven regions across Ukraine were left without power.

Prime Minister Yulia Svyrydenko said it was one of the war's largest attacks on Odesa, where supplies of electricity and water had been knocked out. She said supplies of non-drinking water were being brought in to areas of the city.

Ukraine's interior minister Ihor Klymenko said more than a million households across Ukraine had been left without power and five people had been wounded as a result of the attack.

Ukraine's power grid operator said a "significant number" of households were without power in the southern regions of Odesa and Mykolaiv, and that the Ukrainian-controlled part of the frontline Kherson region was totally without power.

Moscow has regularly bombarded Ukraine's energy system since its 2022 invasion, causing hours of daily blackouts countrywide.

Russia's defense ministry said Saturday it had conducted strikes on Ukrainian energy and military-industrial facilities.