Sir Keir Starmer will travel to Turkey on Tuesday for his final Nato summit amid questions about the UK’s plans to increase defence spending.
Downing Street said the Government remains committed to Nato’s spending target, adding Sir Keir would make clear to allies that the UK’s contribution to Nato “will not waver” in the face of “a new era of threat”.
Officials pointed to a £15 billion boost to defence spending in last week’s long-delayed defence investment plan (Dip), saying Sir Keir would use the summit to “demonstrate how we are turning these pledges into action”.
At home, the Government continues to face questions about whether the Dip is adequately funded and how the UK intends to reach the Nato target of spending 5% of GDP on defence by 2035.
Agreed by allies at last year’s summit in The Hague under pressure from US President Donald Trump, the target includes spending 3.5% of GDP on “core defence” by 2035 and another 1.5% on “resilience” measures such as infrastructure.
Opposition figures have focused on how the Government intends to pay for the Dip, with the Treasury yet to set out funding for £4.7 billion of the £15 billion uplift announced last week.
Commons Defence Committee chairman Tan Dhesi, a Labour MP, has also suggested Sir Keir will arrive at Nato “empty-handed” with no clear path to meeting the commitment to spend 3.5% of GDP on core defence.
Ministers have insisted it is not unusual to wait for a budget to set out funding decisions while new Defence Secretary Dan Jarvis told the Commons on Monday the Government would set out a “clear trajectory” to the 3.5% target at the next spending review.
Mr Jarvis is expected to accompany Sir Keir to the Nato summit this week, along with Foreign Secretary Yvette Cooper.
Ahead of the summit, Sir Keir’s official spokesman said the UK had delivered “the biggest sustained boost to defence spending since the Cold War” and was “committed to the historic 5% Nato target set in 2035”, with the Dip taking Britain to 4.2% already.
Questions on spending are likely to dominate this year’s Nato summit, which begins in the Turkish capital Ankara on Tuesday.
Speaking to reporters ahead of the summit, Nato secretary-general Mark Rutte demanded allies put forward “clear, concrete and credible plans” to reach the target.
Mr Trump has renewed his assault on Nato allies over their defence budgets, claiming last week that the US was bankrolling other countries “without getting any benefit”.
While the US president has repeatedly cast doubt on his commitment to the alliance, tensions over defence funding have been exacerbated by his desire to annexe Greenland – which belongs to fellow Nato member Denmark – and what Mr Trump sees as a lack of support from allies for his war against Iran.
Sir Keir’s official spokesman said the Government rejected Mr Trump’s claims on spending, adding: “The UK has always met its Nato spending commitments and remains one of the top defence spenders in the alliance.”
Asked whether Sir Keir was bracing for a confrontation with Mr Trump, the spokesman said the leaders would be sitting next to each other at Wednesday’s North Atlantic Council meeting, adding: “I expect their conversations to be constructive, as they always are.”
Away from questions about spending and the US commitment to the alliance, Downing Street said Sir Keir would spend the summit “focused on building a stronger and more European Nato than ever before” that could support Ukraine and “face the long-term threat posed by an increasingly reckless and dangerous Russia”.
His spokesman pointed to “escalating attacks on Ukrainian civilians” and Russia’s use of “a medley of hybrid tactics to try to destabilise our societies”, including a surge in cyber and information warfare along with threats at sea and in the air.
The spokesman said the last two years had seen a 30% increase in Russian vessels threatening UK waters while Nato had scrambled fighter jets to intercept Russian aircraft more than 700 times in the same period.
In a demonstration of heightened tensions, British F-35 jets intercepted a Russian patrol aircraft last week after it “repeatedly approached” the UK’s Carrier Strike Group operating in the Arctic.
The Ankara summit is likely to be Sir Keir’s last appearance as Prime Minister at a major international event, coming less than two weeks before he is expected to hand power over to Andy Burnham.
Conservative leader Kemi Badenoch is expected to use a speech in London on Tuesday to argue that the impending transfer of power has turned Westminster into a “pantomime” at a time when “Britain needs seriousness”.
She will say: “We are sending an outgoing Prime Minister who is now completely powerless to that Nato summit, and he is taking with him a defence investment plan which he knows is not fit for purpose.”
The Government has already allowed Mr Burnham’s team to hold “access talks” with civil servants in preparation for power, but Downing Street declined to comment on whether he had been involved in pre-summit discussions.
Mr Burnham has been urged to push for closer defence ties with Europe in the face of questions about America’s commitment to Nato.
Laura Chappell, of the think tank IPPR, said Britain could “no longer build its security strategy around old assumptions about US reliability” and should “look beyond Washington and build stronger alliances closer to home”.
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