Four people died and the Kyiv Pechersk Lavra monastery, a symbol of Ukrainian spiritual and cultural history, caught fire during the heaviest Russian air attack on the capital in two weeks, authorities said on Monday while urging residents to seek shelter.

The new strikes followed Ukrainian President Volodymyr Zelensky's statement on Sunday that he had spoken with US President Donald Trump about efforts to end the more than four-year conflict, ahead of a G7 meeting in France this week.

The central Kyiv Pechersk Lavra monastery, a UNESCO World Heritage site founded in 1051, suffered serious damage from a direct hit, said Tymur Tkachenko, head of the capital's military administration, in a Telegram post.

"This is a UNESCO world heritage site, which is the equivalent, for us in France, as if Notre Dame or Saint Denis had been bombed, which is totally unacceptable," said French Foreign Minister Jean-Noel Barrot upon arriving for a meeting of European Union foreign ministers.

"A brutal assault on our people and our heritage. This is the true face of Russia's Orthodox values," Ukrainian Prime Minister Yulia Svyrydenko said on X.

As towering flames rose over the monastery, residents took shelter underground in the worst Russian attack on Ukraine since early June, when drones and missiles killed more than 20 people and left more than 100 wounded.

Drones and missiles struck several high-rise apartment buildings and damaged electricity lines, leaving some 140,000 residents without power, according to Kyiv authorities.

Four people were killed and 23 were injured, Tkachenko said.

"What more must the Kremlin Antichrist do for the world to realize that decisive action must be taken so that the Russian terror against Ukraine and the very principles of peace come to an end?" Metropolitan Epifaniy, head of the Orthodox Church of Ukraine, said on X.

Neighboring Poland, an EU and NATO member, scrambled fighter jets on Monday against a possible airspace incursion before recalling the alert and saying no sky violation had been recorded, its Armed Forces said in a post on X.

Ukraine would be "urgently initiating" procedures within UNESCO and other international mechanisms to ensure "immediate and adequate responses to this state barbarism," Foreign Minister Andrii Sybiha said on X in reference to the monastery attack, with Estonian foreign minister Margus Tsahkna also condemning the Russian strikes.

Attacks on Ukraine's regions, central Russia

Most of Ukraine's territory was under air raid warnings in the early hours of Monday and Ukrainian drones were being repelled over Russia as both countries continued to exchange strikes.

Five emergency service rescuers were killed and at least another five injured after a second Russian strike hit Kharkiv, Ukraine's second-largest city, Interior Minister Ihor Klymenko said on Telegram, with three people, including a child, wounded in Sumy, according to social media posts by local authorities.

Russia and Ukraine both deny deliberately attacking civilians. Reuters could not independently confirm the reports.

Ukraine has recently intensified attacks on Russian industrial and energy facilities as it tries to deprive Moscow of revenues and hasten an end to the war.

On Monday, three people were killed and another three, including a one-year-old child, were injured in a drone attack on the Russian city of Tula, an industrial cluster south of Moscow, the regional governor said in a Telegram post.

Ukraine-Russia peace deal slowed by Middle East conflict

Ukraine also moved overnight to cut off the Black Sea Crimea peninsula, annexed by Russia in 2014 and already grappling with a fuel crisis, from further supplies by hitting two bridges connecting it to the Russia-controlled areas.

Before his conversation with Trump, Zelenskiy had proposed direct talks with Russian President Vladimir Putin for a ceasefire solution involving the US and Europe - something Britain, Germany and France supported but Putin rebuffed.

The Kremlin said on Sunday that Trump told the Russian leader that ending the conflict in Ukraine was vital and he was ready to help.

Progress towards a peace agreement in Ukraine has been slow, with US officials and mediators concentrating on the conflict in the Middle East. US and Iranian officials said on Sunday they had agreed on a peace framework to end their war, with the pact expected to be officially signed on Friday in Switzerland.