Ukrainian President Volodymyr Zelensky has said it would need an international force of up to 200,000 troops to sustain a ceasefire along the 600 mile (960km) line of contact between the two opposing armies, Russia and Ukraine.

European leaders offered a strong show of support to the Ukrainian president and promised to do more to help his nation.

Following the public clash between Trump and Zelensky, the U.K. and France are trying to broker a compromise solution to end the war.

"Even while Russia talks about peace, they are continuing their relentless aggression," Starmer said at the meeting.

Ukraine said on Sunday it condemned a "breach of territorial sovereignty" by employees of the U.N. nuclear watchdog who visited the Russia-held Zaporizhzhia nuclear power plant in Ukraine via Russian-occupied territory.

International atomic monitors are for the first time traveling through Russian territory rather than Ukraine to reach Europe’s biggest nuclear-power plant, said three diplomats briefed on the matter — a blow to Kyiv’s desire to avoid international recognition of the Kremlin’s ownership claims.