Emmanuel Macron and Keir Starmer will be making back-to-back visits to the White House this week in an attempt to convince US President Donald Trump that Ukrainian and European interests should be taken into account in peace talks with Russia.
Ukraine is set to dominate discussions between the world leaders after Europe rallied behind Ukrainian president Volodymyr Zelenskyy following Mr Trump's pivot towards Russia. Britain and France are reported to be working on a so-called reassurance force of 30,000 men to deter future Russian attacks on Ukraine in the event of a peace deal.
The UK Prime Minister and the French President used a phone call on Sunday afternoon to reaffirm their support for Kyiv three years on from Moscow’s invasion, as the two men prepare to meet Mr Trump separately.
Mr Starmer and Mr Macron agreed to discuss showing “united leadership” in backing Ukraine against Russian aggression on their visits to the US this week, No 10 Downing Street said. They agreed Ukraine must be at the heart of any negotiations regarding its own future.
On the eve of the third anniversary of Russia’s invasion, they discussed how “we must all work together” to put Ukraine in a strong position at “this crucial moment in global security”.
“The Prime Minister repeated the UK’s steadfast commitment to support Ukraine for as long as needed and reiterated the importance of Ukraine being at the centre of any negotiations to end the conflict,” No 10 said. “The UK and Europe must continue stepping up to meet their security needs and show united leadership in support of Ukraine in the face of Russian aggression, which they would both discuss in the US in the coming week."
Britain on Monday announced a move to widen travel sanctions for Kremlin-linked elites in a bid to heap more pressure on Russia as the war in Ukraine enters its fourth year.
Local and federal politicians, as well as managers or directors of large Russian companies, will face exclusion from the UK under the rules, which come on top of existing travel bans on high-profile business figures such as Roman Abramovich.
Mr Macron, one of the few elected leaders in the world who has worked with Mr Trump under his previous mandate, is expected to call on the US President not to rush into striking a deal with Russian President Vladimir Putin.
The visit has been described as a "last-ditch effort for Europeans" by former French ambassador to the US, Gerard Araud. "In order to succeed, [Mr Macron must not] try head-on to change the mind of Trump who, in this situation, always balks, but to demonstrate to him that the participation of Europeans would contribute to the success of a policy whose foundations they do not contest," Mr Araud wrote in magazine Le Point. "Yes to peace, a peace without US troops or funds ... but a peace with security guarantees to Ukraine provided by the Europeans."
A first round of peace talks between Russian and US diplomats took place in Riyadh last week, to be followed by a second meeting on Tuesday. They come amid a deepening row between the US and Ukraine. In recent comments, Mr Trump has pushed for a mineral deal with Ukraine, rejected by Mr Zelenskyy, and echoed Russian arguments blaming Kyiv for provoking the 2022 invasion. After the Ukrainian leader said Mr Trump lived in a "disinformation bubble", his US counterpart responded by mocking Mr Zelenskyy for his previous career as a comedian.
Mr Macron is heading to Washington "with the shared objective of ending the conflict, and also with the concern of supporting Ukraine, of working to strengthen the security of Europe", an Elysee adviser said ahead of the French President's arrival on Sunday evening.
In an hour-long question-and-answer session on social media, Mr Macron said that during his meeting with Mr Trump: "I will tell him: deep down you cannot be weak in the face of President [Putin]. It's not you, it's not what you're made of and it's not in your interests."
In his first meeting with Mr Trump on Thursday, Mr Starmer will discuss "how we as a nation, alongside European allies, play a bigger role in defence and security on the continent", UK Education Secretary Bridget Phillipson told the BBC. Asked whether it was wrong that Mr Trump had spoken directly to Mr Putin this month without consulting Europeans, Ms Phillipson said it was the "right approach" but "any lasting settlement" needs to include Ukraine.

Last week, Mr Macron held a series of meetings with European leaders in Paris in an attempt to strengthen unity around Ukraine but divergences appeared after Mr Starmer's proposal to put boots on the ground was rebuffed by German Chancellor Olaf Scholz. Mr Macron's adviser played down those divisions, saying "we are moving forward as Europeans in a spirit of unity." They added: "With the British, our work relationship is ... extremely dense, extremely intense."
The French leader is believed to be preparing public opinion for increased defence spending despite tight budgetary constraints. Europeans view Russia as an existential threat and fear that a victory in Ukraine would embolden territorial incursions and election meddling across the continent. The EU is expected to impose new sanctions on Russia on Monday.
Mr Trump has called on Nato allies to dramatically increase their defence budgets to 5 per cent of their GDP. The US currently spends 3.4 per cent of its GDP on defence, while France spent 2.1 per cent and the UK 2.3 per cent.
Europe would need to spend around €250 billion ($261.6 billion) annually on defence to secure itself without US support, a sum the bloc could bear given its economic strength, according to a recent study by research institute Bruegel and the Kiel Institute for the World Economy.