Moscow has stepped up strikes on Ukraine’s power and heating infrastructure and conducted another nationwide attack on energy facilities overnight that killed two people.

“The relentless attacks by the Russian Federation on energy infrastructure across Ukraine are depriving an already long-suffering civilian population of adequate warmth, water and electricity in an unbearably bitter and dark winter,” UN rights chief Volker Turk said in a statement.

He said civilians had faced continual bombardment and now had to face temperatures as low as minus 20°C.

“Last night, the Russian Federation again carried out a large-scale attack targeting energy infrastructure across Ukraine. Hundreds of thousands of civilians woke up without electricity and heating,” said Turk.

“The targeting of civilian infrastructure is prohibited under international humanitarian law. I call upon the Russian Federation to immediately cease these attacks.”

The UN high commissioner for human rights said the consequences of such strikes impacted all areas of civilian life.

Turk said millions of households were struggling with a few hours of electricity every day, while unheated schools have been forced to close and access to medical care has been hampered.

Kyiv says the strikes are an attempt to sap morale and weaken Ukrainians’ resistance.

Moscow denies targeting Ukrainian civilians, but thousands have been killed since its full-scale invasion of Ukraine began in February 2022.