European leaders, including Sir Keir Starmer, will join Volodymyr Zelensky for a high-stakes meeting with Donald Trump at the White House on Monday.
The prime minister will travel to Washington alongside several European leaders in a show of solidarity with the Ukrainian president, whose last visit to the Oval Office ended in a disastrous clash with Mr Trump.
The summit comes just days after the US president met Vladimir Putin in Alaska, in which it is understood that the Russian president demanded that Ukraine cede the Donetsk and Luhansk regions as a condition for ending the war.
Mr Trump is said to have privately endorsed the proposal, a move that Kyiv has strongly resisted.
Ukraine’s leader has warned that Russia’s refusal to halt hostilities before agreeing to a settlement would complicate any attempt at securing lasting peace. Speaking ahead of his trip, Mr Zelensky said: “Stopping the killing is a key element of stopping the war.”
Downing Street said Sir Keir and other leaders “stand ready to support this next phase of talks” and will stress that their backing for Ukraine will continue “as long as it takes.”
Who is going to Washington?
European leaders confirmed to be attending include:

The Ukrainian president will travel with a strong backing after participating in a coalition call on Sunday afternoon, hosted by the UK, France, and Germany.
The so-called “coalition of the willing” aims to provide security guarantees, including policing any future peace deal with troops on the ground in Ukraine.
What will be discussed on Monday?
The talks are expected to cover territorial questions, including Russia’s demand for Ukraine to cede Donetsk and Luhansk.
They are also expected to address security guarantees for Ukraine, which could be backed by US air power.
The role of Nato and European allies in enforcing a settlement is likely to be discussed, alongside sanction pressures on Russia.
European leaders want to also ensure Ukraine is at the table for all negotiations.

Speaking alongside Mr Zelensky in Brussels, Ms von der Leyen said: “With regards to any territorial questions in Ukraine, our position is clear: international borders cannot be changed by force.
“These are decisions to be made by Ukraine and Ukraine alone, and these decisions cannot be taken without Ukraine at the table.”
European powers also want to help set up a trilateral meeting between Mr Trump, Mr Putin and Mr Zelensky to make sure Ukraine has a seat at the table to shape its future.
What are Russia’s demands?
At the Alaska summit, Mr Putin reportedly insisted Ukraine must surrender Donetsk and Luhansk in full, abandon its Nato aspirations and declare neutrality. He offered to freeze the front lines in Kherson and Zaporizhzhia, sources close to the meeting told The Independent.
Around 88 per cent of the Donbas is under Russian control. This includes almost all of the Luhansk region and 75 per cent of the Donetsk region.
Russia controls nearly 44,600 square miles or 19 per cent of Ukraine in total, including the Crimean peninsula, according to open-source maps of the battlefield.

Mr Zelensky has rejected the idea of handing over territory, insisting talks must be based on current front lines and begin with a ceasefire.
Mr Trump’s special envoy Steve Witkoff said Mr Putin agreed to allow the US and its European allies to offer Ukraine a security guarantee at his meeting with the US president on Friday.
“We were able to win the following concession: That the United States could offer Article 5-like protection, which is one of the real reasons why Ukraine wants to be in Nato,” Mr Witkoff told CNN.
He added that it “was the first time we had ever heard the Russians agree to that” and called them “game-changing.”
Article 5, at the heart of the 32-member military alliance, states that an armed attack against one or more of the members shall be considered an attack against all members.
Sir Keir commended Mr Trump’s commitment to providing security guarantees to Ukraine, following a meeting of the coalition of the willing on Sunday afternoon.
What happened the last time Zelensky met Trump?
Their previous Oval Office meeting in February ended in a dramatic confrontation.
A planned mineral deal signing ceremony collapsed as Mr Trump and Vice President JD Vance accused Mr Zelensky of being “ungrateful” and “gambling with World War III”.

Mr Zelensky pushed back, insisting there could be “no compromises with a killer” – a reference to Mr Putin.
The meeting was cut short, the joint press conference cancelled, and Mr Trump declared afterwards that Zelensky could “come back when he is ready for peace”, and temporarily suspended aid to Ukraine.