"Today is just one day, but we have received 70 missiles," Zelensky told the UN Security Council on Wednesday while speaking via video link from Kyiv.
He added: "That's the Russian formula of terror. This is all against our energy infrastructure ... Hospitals, schools, transport, residential districts all suffered."
Russia rained missiles on cities across Ukraine on Wednesday, killing at least 10 people, forcing shutdowns of nuclear power plants and cutting water and electricity supplies in many areas, the Reuters news agency reported.
Zelensky said: "We expect a strong reaction from the world to today's Russian terror. We expect the reaction of partners. We expect the reaction of friends - not just observers. We expect the reaction of all those who really recognize the UN Charter."
Putin 'weaponizing winter': US UN envoy
The US ambassador to the United Nations, Linda Thomas-Greenfield, said that Russian President Vladimir Putin was "clearly weaponizing winter to inflict immense suffering on the Ukrainian people" while trying to "freeze the country into submission."
Zelensky said earlier this week that special shelters with electricity, heat and water would be set up for people across the country as winter weather sets in amid persistent Russian strikes on critical energy infrastructure.
Special "invincibility" centres will be set up around Ukraine to provide electricity, heat, water, medicines, and internet and mobile phone connections free of charge and around the clock, Zelensky said in a video address late on Tuesday,
Zelensky said last week that about 10 million people were without power across the country, with emergency blackouts ordered in some areas after days of heavy Russian bombardment of civilian infrastructure.
Ukraine's Prime Minister Denys Shmyhal said this week that some 8,500 power generator sets were being imported to Ukraine daily, according to Reuters.
The World Health Organization warned this week that hundreds of Ukrainian hospitals and healthcare facilities lacked fuel, water and electricity, according to Reuters.
"Ukraine's health system is facing its darkest days in the war so far," Hans Kluge, the WHO regional director for Europe, said in a statement after visiting Ukraine.
"Having endured more than 700 attacks, it is now also a victim of the energy crisis," Kluge added, as quoted by Reuters.
Source: IAR, PAP, Reuters, ukrinform.net, president.gov.ua