The strike was the first large-scale attack using missiles and drones since the US said late in March it had negotiated two ceasefire accords with Russia and Ukraine, including one that would halt strikes on each other's energy infrastructure.
Ukraine's President Volodymyr Zelenskiy said on Sunday ongoing attacks showed Russia did not want to end the three-year-old war.
"Such attacks are Putin's response to all international diplomatic efforts," he said on the Telegram messaging app.
"Each of our partners - America, the whole of Europe, the whole world - has seen that Russia is going to continue to fight and kill.
"Therefore, there can be no easing of pressure. All efforts should be made to ensure security and bring peace," he said.
Andriy Yermak, Zelenskiy's chief of staff, posted a video of firefighters trying to put out fires at badly damaged buildings.
Russian forces used ballistic and cruise missiles launched from both strategic bombers and naval fleets, as well as drones, during the overnight attack, Ukraine's air force said.
Zelenskiy said that in the past week, Russia had launched more than 1460 guided aerial bombs, almost 670 attack drones and more than 30 missiles of various types against Ukraine.
Warnings from the air force of an attack, including regions bordering Poland, forced the neighbouring NATO-member country to scramble aircraft to ensure air safety.
Poland has been on high alert for objects entering its airspace since a stray Ukrainian missile struck the southern Polish village of Przewodow in 2022, killing two people.
In Kyiv, several loud explosions were heard overnight.
Fires broke out in at least three districts of Kyiv, Mayor Vitali Klitschko said in a Telegram post.
"The body of a man killed in an enemy attack was found in Darnytskiy district (of Kyiv). He was on the street, near the epicentre of the explosion," Klitschko said.
He said two civilians had been taken to hospital after they were injured in Darnytskiy, on the eastern bank of the Dnipro River that splits the city.
The Sunday strikes on Kyiv came after officials in the southern region of Mykolaiv reported three people had been injured in Russian strikes.
A day earlier, a Russian attack killed at least 19 people, including nine children, in the Ukrainian city of Kryvyi Rih.
There was no immediate comment from Russia.
Both sides deny targeting civilians in the war that Russia started with a full-scale invasion of its smaller neighbour.
Thousands of civilians have died in the conflict, the vast majority of them Ukrainian.
US President Donald Trump, who took office in January after pledging he would end the war in 24 hours, has sought to broker an end to the conflict.
