With temperatures falling and snow appearing in the capital Kyiv for the first time this winter, authorities were working to restore power across the country after some of the heaviest bombardment of Ukrainian civilian infrastructure during nine months of war.
The United Nations has warned of a humanitarian disaster in Ukraine due to power and water shortages.
"Unfortunately Russia continues to carry out missile strikes on Ukraine's civilian and critical infrastructure. Almost half of our energy system is disabled," Shmyhal said.
He was speaking at a joint news conference with a vice-president of the European Commission, Valdis Dombrovskis, who was visiting Kyiv to discuss emergency European Union financial aid.
President Volodymyr Zelenskiy said earlier about 10 million people were currently without power in a country with a pre-war population of about 44 million.
He said authorities in some areas ordered forced emergency blackouts.
"The aggressor country has officially recognised that its goal is to destroy our energy infrastructure and leave Ukrainians without electricity and heat," Ukraine's grid operator Ukrenergo said on the Telegram messaging app.
It said Russia had launched six large-scale missile attacks on Ukraine's energy infrastructure from October 10 to November 15.
Russia's defence ministry said its forces had used long-range weapons on Thursday to strike defence and industrial facilities, including "missile manufacturing facilities".
Ukrainian forces in the past 24 hours downed two Russian cruise missiles, five air-launched missiles and five Iranian-made Shahed-136 drones, Ukraine's military said.
Reuters was unable to verify battlefield reports.
Russian forces plundered areas of the southern Kherson region that are now back under Ukrainian control following a recent counter-offensive, the deputy head of Zelenskiy's administration said.
"After a trip to the... Kherson region, one thing became clear - our people there need a lot of help. The Russians not only killed and mined but also robbed all the cities and villages. There is practically nothing there," Kyrylo Tymoshenko said on Telegram.
Investigators in liberated areas of Kherson region have uncovered 63 bodies bearing signs of torture after the Russian forces left, Ukraine's interior minister was quoted as saying.
The Ukrainian parliament's human rights commissioner, Dmytro Lubinets, released a video of what he said was a torture chamber used by Russian forces in the Kherson region, including a small room in which he said up to 25 people were kept at a time.
Reuters was unable to verify the claims made by Lubinets and others in the video.
Russia denies its troops deliberately attack civilians or have committed atrocities.
Mass burial sites have been found in other parts previously occupied by Russian troops, including some with civilian bodies showing signs of torture.
Russia, for its part, accused Ukraine of executing more than 10 Russian prisoners of war with direct shots to the head.
The defence ministry was responding to a video circulated on Russian social media which it said showed the execution of Russian POWs.
Russia has moved some troops from Kherson to reinforce its positions in the eastern Donetsk and Luhansk regions.
Ukraine's military said Russian forces had fired artillery on the towns of Bakhmut and nearby Soledar in the Donetsk region, among others.
Russian fire also hit Balakliya in northeastern Kharkiv region, which Ukraine recaptured in September, and Nikopol, a city on the opposite bank of the Kakhovka reservoir from the Zaporizhzhia nuclear power station, the statement said.
In the first known high-level, face-to-face US-Russian contact since the invasion of Ukraine, Central Intelligence Agency chief William Burns delivered a cautionary message this week during talks in the Turkish capital Ankara about the consequences for Russia of any use of nuclear weapons.
Turkish President Tayyip Erdogan told Russian leader Vladimir Putin in a phone call on Friday that the Ankara talks had helped to prevent "uncontrolled" escalation in the field.
