Sir Keir Starmer has urged Donald Trump to provide a “backstop” to any Ukraine peace settlement, insisting it is the only way to deter Russia from attacking the country again.
The Prime Minister’s appeal to the US president came after European leaders gathered in Paris for emergency talks on the future security of the continent following Washington’s push for a deal with Russia.
Sir Keir has said he would be prepared to send peacekeeping troops to Ukraine, but some present at the meeting – including German Chancellor Olaf Scholz – wanted to resist discussing any European force being used to monitor a ceasefire.
Speaking after the summit, the Prime Minister warned that allies – including Britain – will have to “take responsibility” for its security in light of a radically changed US foreign policy.
Countries must commit to bolstering both spending and capability as Ukraine’s fate has become an “existential question” for Europe, he said, after Washington warned it would reduce its defence commitments on the continent.
But Sir Keir insisted a US security guarantee would be the only way to effectively prevent Moscow from attacking the country again in future.
“Europe must play its role, and I’m prepared to consider committing British forces on the ground alongside others if there is a lasting peace agreement,” he said.
“But there must be a US backstop because a US security guarantee is the only way to effectively deter Russia from attacking Ukraine again.”
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The Prime Minister will seek to bridge the gap between Europe and Washington as he flies to America for talks with Mr Trump next week, when he will make the case for US security guarantees.
“At stake is not just the future of Ukraine. It is an existential question for Europe as a whole, and therefore vital for Britain’s national interest,” Sir Keir said on Monday.
“This is a once-in-a-generation moment for the collective security of our own continent. Only a lasting peace in Ukraine that safeguards its sovereignty will deter Putin from further aggression in the future.”
The Prime Minister said that recent statements by the Trump administration “should not come as a surprise” given the president’s long-held view that Europe should “step up” and meet the demands of its own security.
“The issue of burden-sharing is not new, but it is now pressing, and Europeans will have to step up, both in terms of spending and the capabilities that we provide,” he said.
Three hours of emergency talks at the Elysee Palace appeared to have left leaders of Britain, Germany Italy, Poland, Spain, the Netherlands, Denmark, Nato and the EU split on the prospect of European peacekeeping troops.
In an apparent rejection of Sir Keir’s suggestion, Mr Scholz said talk of boots on the ground was “premature,” adding: “This is highly inappropriate, to put it bluntly, and honestly: we don’t even know what the outcome will be.”
The UK Prime Minister, along with European allies, has insisted Ukraine’s voice must be at the heart of any peace deal with Russia amid fears of Washington and Moscow going over the heads of leaders on the continent.
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It comes as US secretary of state Marco Rubio led a delegation to Saudi Arabia for discussions with Russian officials that will look to seek an end to the fighting.
Ukraine has not been invited to the talks and will not accept the outcome if it is not involved, Ukrainian President Volodymyr Zelensky said earlier on Monday, amid fears that Kyiv will remain excluded from discussions.
Senior US officials on their first visit to Europe last week left the impression that Washington was ready to embrace the Kremlin while cold-shouldering many of its old European allies.
Russian foreign minister Sergei Lavrov also appeared to dismiss the prospect of European countries having a say, telling reporters as he arrived in Saudi Arabia: “I don’t know what they have to do at the negotiations table.”
“Obviously, the immediate question is the future of Ukraine, and we must continue to put Ukraine in the strongest possible position whatever happens next, and to make sure that if there is peace, and we all want peace, that it is lasting.”
The Prime Minister has pledged to increase defence spending but is unlikely to go beyond his commitment to set out a plan to increase it to a 2.5% share of the economy despite calls from Mr Trump to reach 5% and Nato secretary general Mark Rutte’s suggestion that allies should spend more than 3%.
The UK currently spends around 2.3% of gross national product on defence.