Rescue workers ended search operations at the devastated building, which was struck this week during Russia's heaviest air attack on the Ukrainian capital in 2026.
"Our first responders ... worked non-stop for more than a day," Zelenskiy said on social media on Friday after visiting the site of the attack in Kyiv's Darnytskyi district, on the left bank of the Dnipro river, placing flowers and talking to rescue workers.
"The Russians practically levelled an entire section of the building with their missile," he said.
Russia, which began its full-scale invasion of Ukraine in February 2022, launched more than 1500 drones and dozens of missiles in attacks across Ukraine this week over two consecutive days, Ukrainian officials said.
Six people were killed in the attacks on Wednesday in western Ukraine, far from the front line.
"A Russia like this can never be normalised - a Russia that deliberately destroys lives and hopes to remain unpunished. Pressure is needed," Zelenskiy said, reiterating appeals to allies to help Ukraine strengthen its air defences.
Kyiv officials announced a day of mourning on Friday to honour the victims, with national flags at half-mast across the city of three million people.
All entertainment events were cancelled or postponed.
The interior ministry said the search and rescue operation at the apartment building lasted more than 28 hours and hundreds of rescuers sifted through 3000 cubic meters of rubble.
City officials said 24 bodies had been recovered from the rubble and about 30 people had been rescued alive. Nearly 50 people were wounded, and about 400 people required psychological support, the interior ministry said.
Zelenskiy has said that, according to initial analysis, a recently manufactured Russian Kh-101 missile struck the building.
Russia did not immediately comment on the strike on the apartment building.
Moscow denies deliberately targeting civilians but during more than four years of war it has frequently hit residential buildings and other civilian infrastructure in air strikes across Ukraine.
Russia and Ukraine have continued to occasionally swap prisoners of war, and 205 from each country returned home Friday.
Zelenskiy said it was the first phase of a planned 1000-for-1000 prisoner swap.
Some of the Ukrainians released had been held in Russian captivity since 2022, he said, and had fought in some of the war's fiercest battles.
Russia's defence ministry confirmed the exchange and thanked the United Arab Emirates for helping broker it.
with AP
