Britain and France are to lead a desperate European attempt to salvage peace hopes in Ukraine, after last week’s explosive meeting between US President Donald Trump and his Ukrainian counterpart Volodymyr Zelenskyy.

Sir Keir Starmer, UK prime minister, said after a summit in London that Europe would step in as intermediaries for Zelenskyy to try to “stop the fighting” and persuade Trump to provide US cover for European troops deployed to secure any ceasefire.

“The UK is prepared to back this with boots on the ground and planes in the air together with others,” he told a press conference on Sunday after a summit in London of 19 international leaders.

Europe “must do the heavy lifting” but the “effort must have strong US backing”, he added.

French President Emmanuel Macron told Le Figaro newspaper after the summit that he and Starmer had proposed an initial truce between Russia and Ukraine “in the air, at sea and on energy infrastructure” that would last a month.

Macron added this approach would have the advantage of verifying Russia’s intentions, and would be easier than overseeing a truce on the ground along the entire front line. 

“In the event of a ceasefire, it would be very difficult to verify that the front is being respected,” he said.

Many European countries are reluctant to commit to sending troops to Ukraine as part of a mission led by the UK and France.

Germany, Spain and Poland are among those which have so far not offered to join “a coalition of the willing”. 

Starmer said “a number of countries have indicated today they want to be part of the plans we are developing” but declined to name them.

He urged more countries to join a peacekeeping effort to persuade Trump that Europe is serious.

“I feel very strongly that unless some move forward we will stay in the same position we are in,” Starmer said. “This is not a moment for more talk. It’s a time to act, to step up and lead.”

Ursula von der Leyen, European Commission president, insisted the EU would step up, saying Ukraine must be turned into “a steel porcupine that is indigestible for potential invaders”.

Starmer and Macron are leading European attempts to persuade Trump to provide a US security guarantee for any peace stabilisation force, but have so far been unsuccessful. 

Italy’s prime minister Giorgia Meloni, who also has strong relations with Trump, is seen in European capitals as another key player. 

The three leaders plan to agree a blueprint for peace with Zelenskyy and then present it to the White House, in an attempt to circumvent the toxic relationship that has developed between the Ukraine president and Trump.

“We have agreed that the UK, France and others will work with Ukraine on a plan to stop the fighting and then discuss those plans with the US,” Starmer said.

Starmer’s allies insisted Zelenskyy was not being sidelined and the UK premier said it would be for Kyiv and Moscow to decide where the “line” for any ceasefire was drawn.

But Europe would take the lead on discussing future security guarantees with Trump.

Trump has insisted that the presence of US companies and workers in Ukraine — exploiting a proposed deal to share proceeds of Ukraine’s mineral wealth — would be enough to deter Russian President Vladimir Putin from launching another attack on his neighbour.

But one ally of Starmer said a US military backstop would still be needed: “If the US has an economic stake, that will of course increase their interest in what happens next. But we don’t see that as a replacement.”

Starmer said UK and US teams were discussing ways in which Trump could help to secure any peace deal, although the US president has always made it clear he sees that as a responsibility of European nations.

The British premier said, however, that he would not be taking “this step down this road” unless he thought there could be a “positive outcome”, including winning Trump’s support. He added: “I don’t accept that the US is an unreliable ally.”

Nato secretary-general Mark Rutte, said as he left the summit that the “debate is ongoing” about whether the US would contribute to security guarantees.

Attendees at the London summit included outgoing German Chancellor Olaf Scholz and Polish Prime Minister Donald Tusk, as well as von der Leyen and Rutte. Canada’s Prime Minister Justin Trudeau and Turkey’s foreign minister Hakan Fidan also attended.

Starmer, Macron and Meloni all made it clear that while Europe needed to do more to defend itself, ultimately the road to peace in Ukraine had to run through the White House. 

“If there are any Europeans who think we can do it on our own, they are clearly wrong,” said one ally of Starmer.

The summit, at Lancaster House in central London, was also an opportunity for leaders to show support to Zelenskyy after the brutal verbal attack on him by Trump and US vice-president JD Vance on Friday.

Zelenskyy was hugged by Starmer on the steps of Downing Street on Saturday and on Sunday he left the summit by helicopter to meet King Charles at his country retreat at Sandringham House.

Meanwhile, Starmer announced £1.6bn of British export guarantees would be provided to supply more than 5,000 air defence missiles for Ukraine, to be made in Belfast.