A late-night strike on a residential neighbourhood of the northeastern Ukrainian city of Kharkiv wounded 21 people, Kyiv said Sunday.
The strike hit late on Saturday, hours after Russian attacks killed five people -- including two children -- in central Ukraine.
The weekend attacks came ahead of a crucial visit by President Volodymyr Zelensky to the United States, where he is due to present proposals on how to end the war and press the West for a green light to use long-range weapons on targets inside Russia.
"Last night, Russia struck Kharkiv again, this time with aerial bombs targeting an ordinary residential building," President Volodymyr Zelensky said on social media.
"As a result, 21 people were injured, including an eight-year-old child and two 17-year-olds," he added.
Regional leader Oleg Synegubov said two people were in critical condition. He said dozens of residents were asleep when the building was struck.
AFP saw rescuers scrambling through a heavily damaged building, with burned-out cars in the parking lot outside, using chainsaws to cut through walls to get to distressed residents in the dark.
"Mama, mama, mama," sobbed one woman, who struggled to breathe and was too scared to descend the stairs.
Rescuers helped her down to find her mother, who hugged her tightly as the woman trembled.
"She is scared," her mother, Oleksandra Ivanivna, told AFP. "It's not the first time."
Kharkiv -- which was home to 1.4 million residents before Russia's invasion -- has seen relentless attacks this year.
"We were asleep. It (the building) was just blown up... the place is a wreck," Ivanivna said.
The city's mayor Igor Terekhov said at the site: "As you can see, there are no military here."
"Every day and every night Kharkiv suffers the hits," he added.
AFP saw an elderly man with his head bandaged being brought to an ambulance, as well as a man whose face was covered in blood, holding a small terrier dog.
Zelensky said the attack showed why his forces needed to use weapons supplied by Western allies to strike deeper into Russian territory, which so far they have refused to authorise.
"We need to strengthen our capabilities to better protect lives and ensure safety. Ukraine needs full long-range capabilities," he said.
"We are working to convince our partners of this. We will continue these discussions next week."
In Washington, he is due to hold talks with Joe Biden, as well as both US presidential hopefuls Kamala Harris and Donald Trump.
Details of Kyiv's so-called "victory plan" have not been made public, but Zelensky has said Ukraine has prepared all of its points.
He has also said Kyiv plans to invite Russia to a second international peace summit in November.
But Moscow this weekend said it would not attend and referred to President Vladimir Putin's conditions to enter talks: that Ukraine surrender four of its regions.
UN Secretary-General Antonio Guterres told CNN Sunday that he does not see a real interest in talks.
"I think both are still betting on the possibility of a military victory," Guterres told CNN in an interview aired Sunday.
"President Zelensky has announced that he has a victory plan to present in the United States... The Russians have clearly indicated that they also have victory (in mind)."
Zelensky will travel to the United States after a summer of intense fighting, with Moscow's troops advancing fast in eastern Ukraine and Kyiv holding on to swathes of Russia's Kursk region.
