Sir Keir Starmer has said Donald Trump's claims British troops were not on the frontline in Afghanistan were "insulting and frankly appalling" - and suggested he should apologise.
Veterans and their families, as well as MPs from all parties, have reacted with fury after the US president said NATO troops stayed "a little off the frontlines" in Afghanistan.
In an interview with Fox News in Davos, Mr Trump repeated his criticism, saying he was not "sure" the military alliance would "be there if we ever needed them".
He added: "We've never needed them. They'll say they sent some troops to Afghanistan... and they did, they stayed a little back, a little off the frontlines."
On Friday afternoon, Sir Keir said: "I consider President Trump's remarks to be insulting and frankly, appalling.
"And I'm not surprised they've caused such hurt to the loved ones of those who were killed or injured."
He added that if he had said something like that, he would "certainly apologise".
Earlier, Downing Street said Mr Trump was "wrong" to diminish the role of NATO and British troops in Afghanistan.
The prime minister's official spokesman said UK forces had served alongside the US and NATO in "sustained combat operations".
Pointing to the 457 British deaths in Afghanistan and the "many hundreds" more who were wounded, he added: "We are incredibly proud of our armed forces and their service and sacrifice will never be forgotten."
America is the only NATO member to have invoked the collective security provisions of its Article 5 clause - that an attack against one member is an attack on all.
Trump's remarks 'the ultimate insult'
Diane Dernie, whose son Ben Parkinson suffered horrific injuries when his vehicle hit a mine in Afghanistan in 2006, said the US president's comments were "the ultimate insult".
Mr Parkinson is widely viewed as the most severely injured British soldier to have survived the war.
The blast left the former lance bombardier with both legs amputated, a twisted spine and brain damage.
His mother said: "I can assure you, the Taliban didn't plant IEDs [improvised explosive devices] miles and miles back from the front line.
"Come and look at us, the life that Ben leads - 19-and-a-half years on, still fighting for his care, still fighting for him to have a decent life, recovering from a recent operation.
"To hear this man say: 'Oh, well, you just fannied about behind the front lines'... It's the ultimate insult."
She said Sir Keir Starmer has "got to stand up for his own armed forces and he's got to absolutely refute what Donald Trump said".
"Call him out," she added.
'We shed blood, sweat and tears'
Defence minister Al Carns said: "I served five tours in Afghanistan, many alongside my American colleagues. We shed blood, sweat and tears together. Not everybody came home.
"These are bonds, I think, forged in fire, protecting the US, our shared interests, but actually protecting democracy overall."
The former commando, who served five tours in Afghanistan and was awarded the Military Cross for gallantry, said Mr Trump's comments were "ridiculous", adding: "Many courageous and honourable service personnel from many nations fought on the front line. Many fought way beyond it."
Robert Dicketts, whose son Oliver Dicketts, 27, was killed while serving with the Parachute Regiment in Afghanistan in 2006, said: "When I read it, I thought, 'What a bloody cheek!'.
"I think my thoughts about Donald Trump are probably unprintable.
"To put it politely, Donald Trump's knowledge of history is lacking considerably."
'Heroes who gave their lives in service of our nation'
The UK suffered the second-highest number of military deaths in the Afghanistan conflict. The US saw 2,461 deaths.
America's allies suffered 1,160 deaths during the conflict - around a third of the total coalition deaths.
Defence Secretary John Healey said: "NATO's Article 5 has only been triggered once. The UK and NATO allies answered the US call. And more than 450 British personnel lost their lives in Afghanistan.
"Those British troops should be remembered for who they were: heroes who gave their lives in service of our nation."
Trump is 'plainly wrongly'
Social care minister Stephen Kinnock also pointed to the fact that the only time NATO's Article 5 clause - a call for allies to come to a member's defence - had been activated "was to go to the aid of the United States after 9/11".
"And many, many British soldiers and many soldiers from other European and NATO allies gave their lives in support of American missions, American-led missions in places like Afghanistan and Iraq," he said.
"I am incredibly proud of our armed forces. They have put their lives on the line for our country. They are the definition of honour and valour and patriotism - and anybody who seeks to criticise what they have done and the sacrifices they make is plainly wrong," Mr Kinnock added.
Ben McBean lost two limbs while serving with the Royal Marines in Afghanistan.
He said: "If someone's speaking the truth, you don't mind, but when it's completely rubbish, it offends you. I was on the frontline every day that I was there.
"I have to live like this. I have to try and raise my family with these injuries. Things are difficult mentally, physically and emotionally, and to have someone who can't even fight sleep sit there and just say 'you guys were slightly further back', along with other nations, is offensive."
'We have always been there'
Dame Emily Thornberry MP, chair of the Commons Foreign Affairs Select Committee, said Mr Trump's comments were "an insult" to the families of those who died and "so much more than a mistake".
Speaking on the BBC's Question Time, Dame Emily said: "How dare he say we weren't on the frontline, how dare he.
"We have always been there whenever the Americans have wanted us; we have always been there."
In a social media post, Liberal Democrat leader Sir Ed Davey MP said: "Trump avoided military service five times.
"How dare he question their sacrifice. Farage and all the others still fawning over Trump should be ashamed."
Josh Babarinde, Liberal Democrat MP for Eastbourne, wrote in a post on X: "[Donald Trump] can go f**k himself.
"Anyone who mocks, demeans or minimises the sacrifices of British troops is no friend of our nation."
"The US is a historic friend of the UK's - but not this guy," he said, referring to Mr Trump.
Conservative Party leader Kemi Badenoch said the sacrifice of British and other NATO troops deserved respect, not denigration, adding his comments were "complete nonsense" which could weaken the NATO alliance.
"I spoke to parents of young men who had lost their lives in Afghanistan, and I think it is a disgrace to denigrate their memory like that," she said.
Mrs Badenoch said there was "too much careless talk from President Trump" and "we mustn't have these sort of throwaway comments that actually weaken the strong relationship between those countries in the alliance".
'I saw the sacrifices made by British soldiers'
Tory MP Ben Obese-Jecty, who served in Afghanistan as a captain in the Royal Yorkshire Regiment, said it was "sad to see our nation's sacrifice, and that of our NATO partners, held so cheaply by the president of the United States".
He said: "I saw first hand the sacrifices made by British soldiers I served alongside in Sangin, where we suffered horrific casualties, as did the US Marines the following year.
"I don't believe US military personnel share the view of President Trump; his words do them a disservice as our closest military allies."
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Former UK ambassador to Afghanistan Sir Nicholas Kay told Sky News the US president was "wrong" and he "clearly does not value and appreciate NATO in the same way he ought to".
"The president is wrong. He is not known for his respect for other people, and he is not known for his accuracy with facts, and I'm afraid this is another example," he said.
Last year, US vice president JD Vance hit back at claims of "disrespecting" British troops who served in Iraq and Afghanistan, after suggesting a potential peacekeeping force in Ukraine would be "20,000 troops from some random country that hasn't fought a war in 30 or 40 years".
At the time, only the UK and France had pledged troops to a potential peacekeeping force.
(c) Sky News 2026: Starmer says Trump's claim UK troops stayed off Afghan frontline 'insulting and frankly appalling'

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