Zelensky was greeted by British Prime Minister Keir Starmer at 10 Downing Street, where he was set to also meet with French President Emmanuel Macron and German Chancellor Friedrich Merz, who arrived earlier for the talks.

"The main focus is our defense in the war, greater cooperation for the security of all of Europe in the area of air defense, and our shared view of diplomatic prospects -- Europe must be part of the negotiations and must be strong," Zelensky said on X ahead of the talks.

The Ukrainian president also said he would meet King Charles III on Monday.

Kyiv is asking its Western allies for more ammunition deliveries for its anti-air defences as Ukraine endures daily Russian strikes. Zelensky is also seeking ways for the allies to further pressure Russia to end the fighting.

On Sunday, Russia fired waves of drones and other munitions at Ukraine, with one of the attacks damaging a nuclear storage facility near the Chernobyl disaster site, Ukrainian officials said.

Radiation levels at the facility remained within normal limits following the attack, although its fuel reception building was "partially destroyed", according to Ukraine's nuclear energy operator, Energoatom.

Moscow and Kyiv have intensified drone strikes on each other in recent months, as US-led diplomatic efforts to end the war -- now in its fifth year -- remain stalled and sidetracked by the conflict in the Middle East.

Russian leader Vladimir Putin has rejected direct peace talks proposed by his Ukrainian counterpart.

Zelensky, in an earlier online post, said Russia had used an Iranian-designed Shahed drone to "hit one of the buildings of the Centralized Spent Fuel Storage Facility" in the Chernobyl exclusion zone.

"As of now, there are no readings exceeding normal background radiation levels. But there is certainly an increase in Russia's brazenness, which long ago went off the charts," he said.

The International Atomic Energy Agency said it was dispatching a team to inspect the damage, calling the incident "deeply concerning".

The facility is located in a remote area of forest around a dozen kilometres (seven miles) from the site of the 1986 Chernobyl nuclear disaster, and is designed to house spent fuel from Ukraine's three active nuclear plants.

- Deadly strikes -

Both sides accused each other of renewed attacks on civilians Sunday.

A Russian bombardment of a public transport stop in Ukraine's southern Zaporizhzhia region left at least two people dead, while a nearby drone strike killed a 56-year-old minibus driver, authorities said.

Separate Russian attacks on the central Dnipropetrovsk region killed two men, governor Oleksandr Ganzha posted on Telegram.

In Russia, a Ukrainian drone strike on a car in the Belgorod border region killed a woman and injured her husband, local authorities said.

Hundreds of thousands of people have been killed and millions forced to flee their homes since Russia launched its full-scale invasion of Ukraine in February 2022.

Russia now occupies around a fifth of its neighbour: the Crimean peninsula, which it annexed in 2014, most of the eastern regions of Donetsk and Lugansk -- collectively referred to as the Donbas -- and large parts of the southern Zaporizhzhia and Kherson regions.

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