More than a million households in Ukraine were left without electricity following Russian strikes on energy facilities across the country, the deputy head of the Ukrainian presidency said.

"As of now, 672,000 subscribers have been disconnected in Khmelnytskyi region, 188,400 in Mykolaiv region, 102,000 in Volyn region, 242,000 in Cherkasy region, 174,790 in Rivne region, 61,913 in Kirovograd region and 10,500 in Odessa region," Kyrylo Tymoshenko said on social media.

Ukrainian President Volodymyr Zelensky said Russia carried out a "massive attack" on Ukraine overnight.

"The aggressor continues to terrorise our country. At night, the enemy launched a massive attack: 36 rockets, most of which were shot down. These are vile strikes on critical objects. Typical tactics of terrorists," Mr Zelensky said on social media.

Ukraine national energy operator Ukrenergo said several western regions are reporting outages.

"[Russians] carried out another missile attack on energy facilities of the main networks of Ukraine's western regions.

"The scale of the damage is comparable or may exceed the consequences of the attack on 10-12 October," Ukrenergo said on social media.

Russian forces rained more than 80 missiles on cities across Ukraine on 10 October, according to the government in Kyiv.

That was in apparent retaliation for an explosion that damaged a key bridge linking the Crimean peninsula to Russia.

Energy restrictions were "forcibly applied" in several regions, including the capital Kyiv and its surrounding region, Ukrenergo said.

"Ukrenergo specialists are taking all measures to restore electricity supply as soon as possible," the operator added.

In western Ukraine, electricity and water supplies were disrupted in parts of the Volyn region, according to its governor.

The city of Khmelnitskyi was without power and the city council called on residents to brace for water shortages.

In Rivne, also in the west, governor Vitaliy Koval said attacks damaged electrical substations.

Power outages were also reported in the southwestern Odesa region following "two missile strikes at the region's energy infrastructure", governor Maksym Marchenko said.

The governor of Kirovograd in central Ukraine called on local businesses and residents to reduce electricity use following attacks on "important" energy facilities in the Kropyvnytskyi and Golovanivskyi districts.

Russia says it repelled Ukrainian offensive

Meanwhile, Russia said its forces had prevented an attempt by Ukraine to break through its line of control in the southern Ukrainian region of Kherson, where it is evacuating civilians in anticipation of a wider Ukrainian counter-offensive.

"All attacks were repulsed, the enemy was pushed back to their initial positions," the Defence Ministry said.

It said that Ukraine's offensive was launched towards the settlements of Piatykhatky, Suhanove, Sablukivka and Bezvodne, on the west side of the Dnipro river.

The ministry's statement said Russian forces had also repelled attacks in the eastern regions of Luhansk and Donetsk.

Reuters could not independently verify battlefield reports.

Russia is under pressure in Kherson as it braces for a Ukrainian push to retake the region.

Ukraine said yesterday that Russian forces had begun actively moving units and equipment from the west to the east bank of the Dnipro river.