Russia's drone assault targeted the southern Ukraine port city of Odesa and the northeastern city of Kharkiv, hitting apartment blocks, officials said on Friday.
The barrage of more than 20 drones injured almost two dozen civilians, including girls aged 17 and 12, Ukraine President Volodymyr Zelenskiy said.
"Russia continues its tactics of targeted terror against our people," Zelenskiy said on messaging app Telegram, urging the United States and the European Union to crank up economic pressure on Russia.
Russia has shown no signs of relenting in its attacks, more than three years after it invaded its neighbour.
It is pressing a summer offensive on parts of the roughly 1000km front line and has kept up long-range strikes that have hit civilian areas.
Kremlin spokesman Dmitry Peskov said the date for the next round peace talks was expected to be agreed upon next week.
Kyiv officials have not recently spoken about resuming talks with Russia, last held when delegations met in Istanbul on June 2, though Ukraine continues to offer a ceasefire and support US-led diplomatic efforts to stop the fighting.
The two rounds of brief talks yielded only agreements on the exchange of prisoners and wounded soldiers.
Ukraine and Russia's defence ministry announced the latest swap on Friday, although they did not specify how many troops were involved.
Zelenskiy said most of those returning home had been in captivity for more than two years.
A fire caused by Russia's night-time strike on Odesa engulfed a four-storey residential building, which partly collapsed and injured three emergency workers.
A separate fire spread across the upper floors of a high-rise, leading to the evacuation of about 600 residents.
In Kharkiv, at least eight drones hit civilian infrastructure, injuring four people, including two children, according to Ukraine's Emergency Service.
Russia launched 80 Shahed and decoy drones overnight, Ukraine's air force said, claiming that air defenses shot down or jammed 70 of them.
