Russia launches massive strikes on Ukraine's energy grid ahead of winter

Russia has launched a widely anticipated attack on Ukraine's power grid, hitting key facilities in Kyiv and other major cities across the country, marking one of the biggest energy assaults in months.

Ukrainian officials and national security experts have been warning about the prospect of a Russian air campaign on its energy infrastructure ahead of winter, fearing another extremely difficult cold snap at a time when the country faces an acute air defense shortage.

Seven people were killed in the latest attacks, officials said Wednesday, with state grid power operator Ukrenergo imposing emergency power cuts in Kyiv and three other regions. Freezing temperatures have been forecast at night in Ukraine's capital over the coming days.

"Russia has launched massive strikes on energy infrastructure," Ukrainian Prime Minister Serhii Koretskyi said Wednesday via Telegram.

"Since the summer, there has been practically no day when the enemy has not attacked energy infrastructure. But such a massive and combined attack has occurred for the first time since the end of the last heating season," Koretskyi said, according to a translation.

Russia's Ministry of Defense said Wednesday that it had delivered a "massive strike" by ground-based high-precision weapons and attack drones at a communication center in Kyiv, as well as Ukraine's energy system facilities and the port infrastructure of Izmail in southwestern part of the Odesa region.

The ministry had said in late August that it was preparing a bombardment of Ukraine's energy infrastructure as part of Russia's response to Ukrainian attacks on its fuel and energy facilities.

Ukrainian President Volodymyr Zelenskyy warned Russian President Vladimir Putin at the United Nations General Assembly last week that Kyiv would make winter deeply painful for Russia if the two sides were unable to agree to an energy truce.

"Ukrainians understand that this winter could be very harsh for us. But in response, we will have no choice but to make it painful for Russia too," Zelenskyy said on Sept. 23.

U.S. President Donald Trump claimed that Russia and Moscow had agreed to halt attacks on energy facilities last month, although both nations swiftly clarified that no formal deal had been finalized.

Trump has also previously urged Zelenskyy to stop targeting Russian oil refineries, saying the attacks are "hurting the world" as fuel supply disruptions continue to prop up U.S. diesel prices.

Matthew Whitaker, the U.S. ambassador to NATO, said that the alliance was prepared for whatever action Russia may take against a NATO country.

"What we have been very clear in communicating back to the Russian side is that we are a defensive alliance. We will defend every inch of NATO territory but at the same time we are not offensive orientated," Whitaker told CNBC's "Squawk Box Europe" on Thursday.

"This is, you know, a situation where because of the lack of success on the battlefield in Ukraine, I think Russia is trying to lash out, but ultimately ... we are prepared," he added.