Ukraine warned there would be emergency blackouts once again in several regions as it repaired damage from missile attacks it said destroyed homes and knocked out power, while Moscow accused Kyiv of attacking deep inside Russia with drones.
A new Russian missile barrage had been anticipated in Ukraine for days and it took place on Monday just as emergency blackouts were due to end, with previous damage repaired.
The strikes, which plunged parts of Ukraine back into freezing darkness with temperatures below zero Celsius (32 Fahrenheit), were the latest in weeks of attacks hitting critical infrastructure.
At least four people were killed, Ukrainian President Volodymyr Zelenskiy said, adding that most of some 70 missiles were shot down.
"In many regions, there will have to be emergency blackouts," he said in a late Monday video address. "We will be doing everything to restore stability."
Moscow has been hitting Ukraine's energy infrastructure roughly weekly since early October in what it says is a bid to degrade Ukraine's military. Ukraine says such attacks are aimed at civilians and constitute war crimes. Moscow denies that.
The United States said it would convene a virtual meeting on Thursday with oil and gas executives to discuss how it can support Ukrainian energy infrastructure, according to a letter seen by Reuters.
U.S. Secretary of State Antony Blinken said Russia would fail in its "current gambit of trying to, in effect, get the Ukrainian people to throw up their hands".
"The point is this, unless and until Russia demonstrates that it's interested in meaningful diplomacy, it can't go anywhere. If and when it does, we'll be the first to be ready to help out," he said at the Wall Street Journal CEO Council in Washington.
Russia says it is waging a "special military operation" in Ukraine to rid it of nationalists and protect Russian-speaking communities. Ukraine and its allies accuse Moscow of an unprovoked war to grab territory from its pro-Western neighbour.
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