The United Kingdom and France are working on a plan to provide a peacekeeping force in Ukraine, if an agreement to pause the war with Russia can be reached.
"You can expect the prime minister to host a second leaders' meeting of the coalition of the willing, building on his Lancaster House summit," Starmer's spokesman told reporters, referring to the London meeting on March 2.
So far only the UK and France have publicly committed to providing troops but other countries are either expected to or to offer other forms of support.
Russia has shown no sign of agreeing to such a force while US President Donald Trump has far offered few assurances of providing a US security guarantee.
The UK and France are involved in diplomatic and military talks to discuss what that force would look like and what its responsibilities could be.
UK defence minister John Healey and the UK's Chief of the Defence Staff Tony Radakin are both expected in France this week for separate talks on Ukraine while the foreign minister David Lammy will hold discussions with G7 colleagues in Canada.
A French army official said on Monday that military officials from more than 30 countries will take part in Paris talks on the creation of an international security force for Ukraine.
The long list of participants in Tuesday's discussions will also include Asian and Oceania countries that will join remotely, the French official said.
The French military official spoke to the Associated Press on condition of anonymity to discuss the blueprint for the force that is shrouded in secrecy and the Paris talks that will consider it.
The force being envisaged by France and the UK could include heavy weaponry and weapons stockpiles that could be rushed within hours or days to aid in Ukraine's defence in the event of a Russian attack that shatters any truce, the official said.
The French-UK blueprint will be presented to military officials from more than 30 countries in the first part of Tuesday's talks, the official said.
The talks' second part will include "more precise and concrete" discussions where the participants will be invited to say whether and how their militaries might be able to contribute, the official said.
"It's not 'This is what we need'," the official said. "It's more, 'What are you bringing to the pot?'".
The official stressed however that the ultimate decision on whether countries take part in the force would be taken at a political level by government leaders.
Chiefs of staff - or, in Canada's case, their representative - from nearly all of 32 countries of the NATO military alliance will attend the Paris discussions.
Three NATO members will be absent but were invited: the United States, Croatia and Montenegro, the official said.
Also attending will be the chiefs of staff of Ireland and Cyprus and a representative from Austria - all countries that are not NATO members but are in the European Union.
Australia and New Zealand as well as Japan and South Korea will listen into the talks remotely, the official said.
Ukraine will be represented by a military official who is also a member of the country's security and defence council.
Separately, US Middle East envoy Steve Witkoff said on Monday the US expects substantial progress in talks with Ukraine this week and hopes that a deal on critical minerals can be signed.
US negotiators were set to meet with a Ukrainian delegation this week in Saudi Arabia.
"I think that we're going over there with an expectation that we're going to make substantial progress," Witkoff told Fox News.
Asked if he thought Ukrainian President Volodymyr Zelenskiy would return to the US to sign a minerals deal this week, Witkoff said, "I am really hopeful. All the signs are very, very positive".
Witkoff said among important items on the table will be security protocols for the Ukrainian side and territorial issues.
Intelligence sharing also will be discussed at this week's meetings, Witkoff said just before leaving for the Middle East for talks on the Gaza Strip.
However, he said, the US never shut off intelligence for anything defensive that Ukrainian forces needed.
with AP
