The five leaders, who are calling on Russia to accept an unconditional ceasefire in Ukraine to create space for talks, held a phone call with US President Donald Trump on Saturday to discuss their peace efforts, Ukraine's foreign minister said.
"Ukraine and all allies are ready for a full unconditional ceasefire on land, air, and at sea for at least 30 days starting already on Monday," Foreign Minister Andrii Sybiha wrote on X, posting a photograph of the five men seated side by side and huddled around a table.
The visit by British Prime Minister Keir Starmer, French President Emmanuel Macron, German Chancellor Friedrich Merz and Polish Prime Minister Donald Tusk is the first time the leaders of the four countries have travelled together to Ukraine.
Before the summit began, a French diplomatic source said the leaders would discuss a US and European proposal for a 30-day ceasefire that if refused by Moscow would see them jointly impose new sanctions.
Zelenskiy accompanied the leaders as they paid their respects at a memorial in central Kyiv to honour Ukrainian soldiers killed in the war.
The visit comes at an unpredictable diplomatic moment in Russia's more than three-year-long war against Ukraine.
US President Donald Trump is pushing for a rapid peace after tearing up the policies of his predecessor since entering the White House in January.
After engaging with Russian officials, clashing publicly with Zelenskiy and briefly cutting vital military aid to Ukraine, the Trump administration has patched up ties with Kyiv and signed a mineral resources deal.
Trump has also shifted his tone, signalling growing frustration with what Washington views as Putin's foot-dragging over a ceasefire.
Trump has threatened to step up sanctions against Russia, but he has also said he could abandon the peace effort if there is no breakthrough.
He called on Thursday for a 30-day ceasefire and Zelenskiy said he would be ready to implement it immediately.
The European Union has joined the call for a 30-day ceasefire.
Kremlin spokesman Dmitry Peskov suggested that Western military assistance for Ukraine would have to stop in order for a temporary ceasefire to happen, "otherwise it will be an advantage for Ukraine".
Western military aid has been vital for Ukraine since Russia's full-scale invasion in February 2022.
Putin hosted Chinese President Xi Jinping and other leaders at a Red Square military parade on Friday to mark the 80th anniversary of the Soviet Union's victory over Nazi Germany in World War II, sending a defiant message that he is not isolated.
On the same day, European ministers voiced support for a special tribunal to prosecute the Russian president and his officials for crimes of aggression, showing support for Zelenskiy, who on Thursday poured scorn on Putin for planning a "parade of bile and lies".
On the eve of the summit, the US embassy in Kyiv warned of a "potentially significant" air attack in the coming days.
The leaders are expected to host a virtual meeting with other leaders to update them on progress on a future coalition of an air, land and maritime force that would help regenerate Ukraine's armed forces after any peace deal.
The visit falls on the final day of a May 8-10 ceasefire declared by Putin that Ukraine did not accept, denouncing it as a sham.
Both sides have accused each other of violating it.
