UK and NATO allies need to prepare to defend Europe without US, MPs say

The UK and its NATO allies in Europe must prepare for a "worst case scenario" of the US not defending them in a crisis, an influential committee of peers and MPs has warned.

Tensions between Donald Trump's administration and Sir Keir Starmer's government could also compromise the reliability of critical pillars of UK national security, including the maintenance of Trident missiles used in the navy's nuclear deterrent submarines, intelligence sharing and access to programmes such as the F-35 jet, it said in a report.

The Joint Committee on the National Security Strategy urged London to "plan to move away from a bilateral relationship with the United States that is so dependent on the latter for nuclear and intelligence operations, and conventional defence".

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It also advised the UK, Europe and Canada to develop a plan "for a transition towards greater European leadership of NATO".

The intervention, published on Friday, came as President Trump again lambasted his allies - and the UK in particular - for choosing not to join his war against Iran.

He mocked the Royal Navy's two aircraft carriers as "toys", while accusing fellow NATO countries of having "done absolutely nothing" to help combat the Iranian regime.

Posting on social media, the president added: "The USA needs nothing from NATO, but 'never forget' this very important point in time."

The comment is a further signal that Washington's support to the transatlantic alliance under Article 5 of its founding treaty on collective defence - where an attack on one ally is deemed to be an attack on all - cannot be guaranteed.

Mr Trump has already repeatedly dismissed Mr Starmer as not being like Winston Churchill.

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The increased unpredictability of the White House's security priorities is upending NATO assumptions on the defence of Europe - which has always been built around a belief that the US armed forces would be the dominant power on the side of the allies in a war.

The Supreme Allied Commander Europe - the top operational commander in the alliance - has only ever been an American, while the US military provides critical elements to any fight such as satellite feeds, electronic warfare jammers and overwhelming mass.

It means a European-only force would be a lot less capable.

The committee - which was assessing the UK's National Security Strategy, published last June - said it was important for the government to continue to collaborate with the US where practical.

But it must also "develop a clear plan, along with other European allies, for a transition towards greater European leadership of NATO".

"Preparing for a 'worst-case scenario' whereby Europe can no longer rely on US support in the event of a crisis, the Government must work with European partners to invest in its own capabilities to offset this potential withdrawal," the committee added.

Britain is uniquely exposed to any weakening in this transatlantic bond because of its close security and defence partnership with the US, developed over decades and based on the "special relationship".

The committee listed areas of particular importance, including the UK's dependence on the US for maintenance of its Trident missiles, intelligence sharing arrangements, delivery of the F-35 fast jet programme, and a new plan to build attack submarines.

But it warned of the potential for Mr Trump to use any leverage he has against allies if they do something he does not like.

Referring to Britain's reliance on the US in various defence and security domains, the report said: "There are demonstrable areas of tension in the UK-US relationship that may compromise the reliability of these dependencies in the near future."

(c) Sky News 2026: UK and NATO allies need to prepare to defend Europe without US, MPs say