As of this morning 1,940 apartment buildings in Ukraine's capital Kyiv were still without heating after a Russian air attack this week, Mayor Vitali Klitschko said.
Mr Klitschko added on the Telegram messaging app that the buildings were being re-connected for the second time after an earlier Russian attack on 9 January.
Earlier this week, Russia launched a combined drone and missile attack on Ukraine, knocking out power and heating supplies to thousands of apartment buildings in Kyiv amid freezing temperatures.
On Tuesday, Ukrainian President Volodymyr Zelensky said that more than one million households in Kyiv were without power after the Russian air strikes.
The strikes also left the parliament building in Kyiv without electricity, heating and water, its speaker said.
The strikes also damaged energy and other critical infrastructure in Vinnytsia, Dnipro, Odesa, Zaporizhzhia, Poltava and Sumy regions.
It was the second major attack on the energy sector and other critical infrastructure in the Ukrainian capital so far this month as temperatures hover well below 0C.
Russia, which launched its Ukraine offensive in February 2022, says its strikes are aimed at energy infrastructure fuelling Ukraine's "military-industrial complex".
Kyiv says the strikes are a war crime designed to wear down its civilian population.
The power cuts in Ukraine come as a fire broke out at an oil depot in Russia's central Penza region as a result of debris falling from a downed drone, the regional governor said today.
The air defence system downed four drones in total with the fragments of one drone falling on the territory of the oil depot in the city of Penza, the region's governor, Oleg Melnichenko, wrote on Telegram.
He added that emergency services were working there and said that there were no injuries or victims.
Meanwhile, Ukrainian, US and Russian officials will hold security talks in the United Arab Emirates today, the Kremlin said, following a meeting of top US negotiators with President Vladimir Putin in Moscow on a US-drafted plan to end the Ukraine war.
Diplomatic efforts to end Europe's deadliest conflict since World War II have gained pace in recent months, though Moscow and Kyiv remain at odds over the key issue of territory in a post-war settlement.
