The pair are leading attempts to put together a group of countries who would contribute in different ways to the effort, referred to as a “coalition of the willing”.
“A number of countries have indicated that they want to be part of the plan that we are developing,” said Starmer, without naming the nations.
“I’ll leave them to make their own statements about exactly how they want to make that contribution,” he added.
Starmer said that those willing “will intensify planning now with real urgency”.
“Not every nation will feel able to contribute, but that can’t mean that we sit back,” he added.
US President Donald Trump has yet to commit to any security guarantees but Starmer added that discussions were on the basis “that it will have US backing”.
“I would not be taking this step down this road if I didn’t think that it was something that would yield a positive outcome in terms of ensuring that we move together – Ukraine, Europe, UK and US,” he added.
Starmer also said America was “not an unreliable ally”.
Italian Prime Minister Giorgia Meloni appeared to downplay the possibility of Italy contributing peacekeepers, saying “the presence of Italian troops in Ukraine at this stage has never been on the agenda”.
“I see this as a solution that risks being very complex and probably less decisive than others,” she said.
Starmer also announced a deal allowing Ukraine to use £1.6 billion (NZ$3.6b) of UK export finance to buy more than 5000 air defence missiles.
– Agence France-Presse