Ukrainian President Volodymyr Zelenskyy on Sunday praised his country's air defence forces, after the capital Kyiv saw the largest drone attack since the beginning of the Russian invasion.
The overnight attack killed two people and wounded three others.
The latest drone attack came as Russia has intensified aerial strikes on the capital this month, and warned the West against escalating the conflict after the United States agreed to greenlight F-16 deliveries.
Ukraine said the latest attack in Kyiv was "the most important" of the invasion, with more than forty out of 54 drones targeting the capital.
"Every time you shoot down enemy drones and missiles, lives are saved... you are heroes!" Zelenskyy told his air defence forces on Sunday morning, also thanking rescuers.
This was the 14th drone attack on the Ukrainian capital by Russia this month.
"People are in shock. There's a lot of damage, the windows were broken, the roof was damaged," said Sergei Movchan, a 50-year-old resident whose house was damaged by debris.
Kyiv had been relatively spared since the beginning of the year, but in May its residents have had to live with almost nightly air raid sirens and thundering explosions.
"Russians are intimidating us. But I think it's the agony of their regime," Movchan said.
- 'Record' number -
In Kyiv the air raid alert lasted more than five hours as the attack was carried out in several waves, city authorities said.
The Kyiv military administration said that "more than 40 Russian drones were destroyed by air defence" systems in the "most important drone attack against the capital since the start of the invasion" in February 2022.
Authorities reported that two killed and three others wounded as debris of the downed drones fell in several districts.
Kyiv's mayor, Vitali Klitschko described the assault as "massive" with drones "arriving from several directions at once".
Sunday was to be celebrated as Kyiv's city day, usually marked by street concerts and celebrations.
"Today the enemy decided to 'congratulate' the population on Kyiv Day with the help of their killer drones," the authorities said.
"Kyiv has stood up. Kyiv is strong and powerful," said presidential chief of staff Andriy Yermak.
Ukraine's air force said that "a record" of 54 drones were launched from the regions of Briansk and Krasnodar in Russia, adding that 52 were destroyed.
Moscow was targeting "military installations and critical infrastructure in the centre of the country and in particular the Kyiv region", it said.
- 'Playing with fire' -
As the drone war rages, Russia has over the past few weeks seen its own territory attacked as well, blaming Kyiv for dozens of artillery, mortar and drone strikes on the southern Belgorod region.
Ukraine has denied most of the accusations.
The reports of attacks come at a time when Kyiv says it is finalising plans for a counter-offensive to recover lost territory, including the Crimea peninsula which was annexed in 2014.
Most drones target Russian regions bordering Ukraine but they have sometimes reached hundreds of kilometres inside Russia, including on the Kremlin itself.
On Saturday, a building from where an energy pipeline is administered was damaged by two drones in western Russia, governor Mikhail Vedernikov said.
The past week also saw an unprecedented two-day incursion from Ukraine claimed by two anti-Kremlin groups, with Russia using its air force and artillery to push back the fighters.
Moscow has accused Kyiv -- and its Western supporters -- of the escalating number of attacks and sabotage operations, including of the most spectacular against the Kremlin on May 3, but Ukraine has denied involvement.
Foreign Minister Sergei Lavrov on Sunday said Western nations were "playing with fire" by agreeing to supply Ukraine with advanced US F-16 fighter jets.
It was "an unacceptable escalation" of the conflict, Lavrov said in an excerpt from a Russian TV interview posted on social media, denouncing an attempt to "weaken Russia" by "Washington, London and their satellites in the EU".