When UK would deploy nuclear weapons as Donald Trump makes chilling claim about 'greatest threat to humanity'

It's a scenario most of us would rather not think about, but here is what would happen in the event of the United Kingdom deploying their nuclear arsenal.

In the not so distant past, the prospect of nuclear annihilation seemed like a bygone relic of the Cold War, but not anymore.

In fact, being vaporised in a fiery mushroom cloud appears to be back in fashion, with US President Donald Trump calling nuclear war the 'greatest threat to humanity' in a recent interview.

"We spend a lot of money of nuclear weapons - the level of destruction is beyond anything you can imagine," he told Fox News of America's 5,044 warheads.

"It's just bad that you have to spend all this money on something that if it's used, it's probably the end of the world."

Donald Trump has branded the prospect of nuclear war the 'greatest threat to humanity' (Andrew Harnik/Getty Images)

So let us be pessimists for a moment and imagine the worst case scenario, what would happen if the UK ever found itself in a situation where its nuclear weapons were being deployed?

When and how would the UK deploy its nuclear weapons?

As of 2024, public records state that the UK has around 225 warheads, of which 120 are operationally available for deployment as part of its Trident programme, and ranks fifth out of nine in terms of nuclear capability.

The US ranks second, behind Russia who have around 5,580 warheads.

Only the Prime Minister can authorise the use of UK nuclear weapons

Although the UK is a member of NATO, which notably includes the Article 5 clause - 'if a NATO member is attacked, all other members will consider it an attack on themselves' - the alliance cannot call for nuclear weapons to be used in a collective response. This responsibility falls on the UK Prime Minister - currently Keir Starmer - to authorise the use of Trident.

Authorisation of the UK's nuclear weapons comes from the sitting Prime Minister, currently Keir Starmer (Dan Kitwood/Getty Images)

Under what circumstance would the UK use its nuclear weapons?

According to the Government website, the primary function of the UK's nuclear weapons is as a deterrent.

"We would consider using our nuclear weapons only in extreme circumstances of self-defence, including the defence of our NATO allies," UK guidelines state.

"The UK maintains only the minimum amount of destructive power needed to guarantee our deterrent remains credible and effective against the full range of state nuclear threats," the website added, stating that key details of our nuclear deterrent are kept 'deliberately ambiguous' to maximise its effectiveness.

Trident: never used or 'always in use'?

Thankfully the UK has never been in a position in which its needed to use nuclear weapons, however the defence ministry states this doesn't mean the weapons aren't technically 'in use'.

In fact, the position of the UK government is that our nuclear weapons are always in use as they 'protect us every hour of every day'.

"By providing a credible and effective response option to extreme aggression, our nuclear deterrent reduces the likelihood of such an attack taking place," the Ministry of Defence adds.

What is the ultimate goal of the UK's nuclear weapons programme?

If countries having nuclear weapons in order to prevent other nations' use of said nuclear weapons sounds like a catch-22, that's because it is.

With the uneasy prospect of mutually assured destruction holding, for now.

However this doesn't mean the UK isn't hopeful for a future without the need for nukes, with the nation a signatory of the 1968 Treaty on the Non-Proliferation of Nuclear Weapons (NPT). The ultimate goal of the NPT is to prevent the spread of nuclear weapons, promote peaceful uses of nuclear energy and ultimately achieve global nuclear disarmament.