Russia launched a major overnight missile and drone attack on Ukraine that killed at least three people - including a four-year-old child.
Officials say Russia fired more than 650 drones and three dozen missiles in an assault that began during the night and stretched into daylight hours Tuesday.
Ukrainian President Volodymyr Zelenskyy said the barrage struck homes and the power grid in 13 regions across Ukraine, causing widespread outages in bitter temperatures.
It comes a day after he described recent progress towards a peace deal as "quite solid".
The bombardment demonstrated Russian President Vladimir Putin's intention of pursuing the invasion of Ukraine, Mr Zelenskyy said in an online post.
Ukrainian and European officials have said Putin is not sincerely engaging with US-led peace efforts.
The attack "is an extremely clear signal of Russian priorities," Mr Zelenskyy said.
"A strike before Christmas, when people want to be with their families, at home, in safety. A strike, in fact, in the midst of negotiations that are being conducted to end this war. Putin cannot accept the fact that we must stop killing."
US President Donald Trump has for months been pressing for a peace agreement, but the negotiations have become entangled in the very different demands from Moscow and Kyiv.
US envoy Steve Witkoff described talks in Florida with Ukrainian and European representatives as "productive and constructive".
Trump was less effusive on Monday, saying, "The talks are going along."
Initial reports from Ukrainian emergency services said the child died in Ukraine's northwestern Zhytomyr region, while a drone killed a woman in the Kyiv region, and another civilian death was recorded in the western Khmelnytskyi region, according to Mr Zelenskyy.
Russia launched 635 drones of various types and 38 missiles, Ukraine's air force said. Air defences stopped 587 drones and 34 missiles, it said.
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Polish and allied fighter jets were deployed after the Russian airstrikes towards western Ukraine, near Poland's border.
"Fighter jets were scrambled, and ground-based air-defence and radar reconnaissance systems were put on heightened readiness," the operational command of Poland's armed forces said.
It was the ninth large-scale Russian attack on Ukraine's energy system this year and left multiple regions in the west without power, while emergency power outages were in place across the country, acting Energy Minister Artem Nekraso said. Work to restore power would begin as soon as the security situation permitted, he said.
Ukraine's largest private energy supplier, DTEK, said the attack targeted thermal power stations in what it said was the seventh major strike on the company's facilities since October.
DTEK's thermal power plants have been hit more than 220 times since Russia's full-scale invasion began in February 2022. Those attacks have killed four workers and wounded 59.
Authorities in the western regions of Rivne, Ternopil and Lviv, as well as the northern Sumy region, reported damage to energy infrastructure or power outages after the attack.
In the southern Odesa region, Russia struck energy, port, transport, industrial and residential infrastructure, according to regional head Oleh Kiper.
A merchant ship and over 120 homes were damaged, he said.
(c) Sky News 2025: Russia launches major deadly missile and drone attack on Ukraine
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