Multiple rounds of loud explosions were heard in the Ukrainian capital throughout the early hours of the morning, AFP journalists reported, in a barrage the air force said involved 600 drones and 90 missiles.

Kyiv Mayor Vitali Klitschko said two people had been killed in the capital and dozens wounded, while the head of the surrounding Kyiv region said two people had also been killed there.

Air defences intercepted 549 of the drones and 55 missiles, the air force said. Ukraine's President Volodymyr Zelensky said Russia had fired its nuclear-capable hypersonic Oreshnik missile and wounded 69 people in the capital in the barrage.

"Three Russian missiles against a water supply facility, a market burnt down, dozens of residential buildings damaged, several ordinary schools, and he (Putin) launched his 'Oreshnik' against Bila Tserkva (in central Ukraine)," Zelensky said on Telegram.

"They are genuinely deranged."

Russia's army confirmed it had launched the Oreshnik at Ukraine, saying it was "in response to Ukraine's terrorist attacks on civilian infrastructure on Russian territory".

The blasts in the capital caused a residential building near the government district to shake, while dozens of people took shelter in an underground metro station in the city centre.

"Russia hit a dead-end on the battlefield, so it terrorises Ukraine with deliberate strikes on city centres," the European Union's top diplomat, Kaja Kallas, wrote on X.

"Moscow reportedly using Oreshnik intermediate-range ballistic missiles -- systems designed to carry nuclear warheads -- is a political scare-tactic and reckless nuclear-brinkmanship."

French President Emmanuel Macron joined the criticism, saying the strikes signalled "the dead end of Russia's war of aggression".

Klitschko said damage had been recorded in every district of Kyiv, adding that a strike on a school had sparked a fire and another on a business centre led to people being trapped in a shelter.

The building housing the studio of German broadcaster ARD was also damaged, the outlet said in a statement.

Ukrainian authorities said Russian strikes had also wounded 12 people in the Kharkiv region, 11 in the Cherkasy region and seven in the Dnipropetrovsk region.

- Retaliation -

Ukraine had been expecting a major attack after its own forces launched a drone barrage on Starobilsk, in the Russian-occupied east of the country, which Moscow said hit a college dormitory and killed at least 18 people.

Launched overnight on Thursday to Friday, the drone salvo -- one of Ukraine's deadliest such strikes in months -- also wounded 42 in the city, located in the occupied Lugansk region.

Ukraine denied targeting civilians, saying it had hit a Russian drone unit stationed in the area.

Russia's foreign ministry said on Friday those responsible would face "inevitable and severe punishment".

Ukraine regularly targets Russian-controlled areas of the country with drones, arguing that the strikes are retaliation for Russian attacks.

- Occupied territory -

Russia's emergency ministry said on Saturday it had pulled two more bodies from the rubble of the dormitory in Starobilsk, taking the death toll to 18.

Video shared by the ministry showed dozens of rescuers sifting through what remained of a section of the five-storey building.

Most of those killed and missing were young women born between 2003 and 2008, according to a list of casualties published by the Moscow-backed governor of occupied Lugansk, Leonid Pasechnik.

Starobilsk lies about 65 kilometres (40 miles) from the front line in eastern Ukraine. It was captured by Russian forces in the early months of the offensive in 2022.

Kyiv has recently expanded its drone capabilities and stepped up strikes on undisputed Russian territory, including residential areas and oil export infrastructure.

Moscow has hit Ukraine almost daily with barrages of missiles and drones since launching its full-scale invasion of the country in 2022, also hitting infrastructure and causing civilian deaths. It denies targeting civilians.

US-led efforts to negotiate an end to more than four years of war have slowed in recent months, with Washington's attention diverted towards its conflict in the Middle East.

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