Russia hammered Ukrainian energy facilities in a massive aerial attack on Friday that President Volodymyr Zelenskiy said was one of the largest yet on the ailing grid and evidence of why Kyiv needed more Western support before any peace with Russia.

Russia's 12th major assault on the energy system this year damaged power facilities in several Ukrainian regions and forced authorities to impose even longer electricity cuts for millions of civilians, the national grid operator said.

With winter temperatures currently around -6 degrees Celsius, the strikes increase pressure on Ukraine at an unpredictable moment with Donald Trump set to return to the White House next month, vowing to end the war quickly.

"This is (Russian President Vladimir) Putin's plan for 'peace' – to destroy everything. This is how he wants 'negotiations' – terrorising millions of people," Zelenskiy said on X.

"A strong reaction from the world is needed: a massive strike – a massive reaction."

Russia launched 93 missiles, including one manufactured in North Korea, and nearly 200 drones during the attack, Zelenskiy said. Air defences intercepted 81 of the missiles, including 11 shot down by F-16 fighter jets, he added.

The full extent of the damage was hard to assess. After repeated Russian attacks, officials reveal little detailed information about the state of the network.

Six unspecified energy facilities were damaged in the western region of Lviv that borders Poland, officials said.

An industry source told Reuters the attack had targeted power substations and that there had been more strikes on gas infrastructure than in past assaults.

Unspecified equipment at thermal power plants sustained serious damage, according to DTEK, Ukraine's biggest private power provider, which has been battered by the strikes since Russia's February 2022 invasion.