Russia launched a massive attack on Ukraine's energy infrastructure, which authorities said was the twelfth large-scale attack on energy facilities this year.
93 missiles and more than 200 drones were used, but 81 missiles were shot down, according to President Volodymyr Zelensky.
The strikes targeted sites in western Ukraine, and energy facilities were damaged in several areas, some of them seriously. Authorities in Ivano-Frankivsk said this was the worst attack the region had witnessed so far.
Russia said the attack was in response to a Ukrainian strike on a military air base in southwestern Russia using American-made missiles, which US President-elect Donald Trump described as “crazy.”
In an interview with Time magazine on Thursday. On the occasion of his selection as Person of the Year, Trump said that he “strongly” disagreed with American-made missiles targeting sites in Russia.
He added: “We are only escalating this war and making it worse.”
The Kremlin said on Friday that Trump's comments were “fully consistent” with Moscow's position.
“This impresses us,” Kremlin spokesman Dmitry Peskov told reporters. “It is clear that Trump understands exactly what is escalating the situation.”
Trump also told Time magazine that he wants to reach a deal to end the war, and the only way to do that is to “not give up.”
The Russian retaliatory attacks came on the coldest day of the Ukrainian winter so far, with temperatures reaching around -6 degrees Celsius.
In addition to the damage to the Ivano-Frankivsk region, energy facilities and infrastructure in the Lviv and Ternopil regions were damaged.
No vital or residential infrastructure was damaged in the Kiev region, according to Governor Ruslan Kravchenko.
Five out of nine nuclear reactor units operating in the country operate at low capacity.
As a result of the attack, the national energy company Ukrainergo was forced to increase restrictions on energy supplies on Friday, as power outages began in all regions.
Okrnergo added that electricity will be imported during the day on Friday from Poland, Romania, Slovakia, Hungary and Moldova.