The strikes have left thousands without heating as temperatures plunge to minus 20°C.
Ukraine’s defence ministry said on X that Russia launched more than 70 missiles and 450 attack drones.
In Kyiv, where air raid sirens sounded for more than seven hours, three people were injured.
Missiles struck residential buildings, a petrol station and critical energy infrastructure.
Mayor Vitali Klitschko said nearly 1,200 apartment blocks were left without heating, following the attacks.
Meanwhile, Kharkiv endured more than three hours of intensive shelling.
Mayor Ihor Terekhov said on Telegram: "The strikes are deliberately targeting energy infrastructure. The goal is obvious: to inflict maximum damage and leave the city without heat during severe frost."
Some 820 buildings had to have their heating systems drained to prevent pipes freezing.
"I understand how difficult this is in twenty-degree frost. But an unprecedented attack on critical infrastructure leaves no other option." he said.
Ukrainian Foreign Minister Andrii Sybiha described the attacks as "genocidal", saying Russia had waited for temperatures to drop before launching the assault.
He said the strikes primarily targeted energy infrastructure and residential areas.
The attacks come days after US President Donald Trump announced on 29 January that Russian President Vladimir Putin had assured him Moscow would not strike Kyiv or other Ukrainian cities.
The Kremlin later clarified this commitment applied only until 1 February.
(ał)
Source: PAP