Trident is the UK's submarine-based nuclear deterrent. It is being renewed with new Dreadnought-class submarines at a cost running into many tens of billions of pounds over its lifetime.

How much would cancelling Trident save?

The Greens estimate roughly £3bn a year; the exact figure depends on how much of the renewal programme is cancelled and over what period.

Is this government policy?

No — it's a Green Party proposal. The main parties support renewing the deterrent, and renewal is under way.

The Greens' plan to cancel Trident: what it means

What's being proposed

The Green Party would cancel the renewal of Trident — the UK's submarine-based nuclear deterrent — and pursue multilateral and unilateral nuclear disarmament. The party argues that nuclear weapons are enormously expensive, strategically questionable and morally wrong, and that the money would be better spent on conventional defence, public services and climate resilience. The Greens have estimated that not proceeding would free up in the region of £3bn a year.

Where it comes from

The UK is renewing its four Vanguard-class submarines with the new Dreadnought class, a programme whose whole-life cost runs into many tens of billions of pounds over decades. Opposition to nuclear weapons is a long-standing Green position. Critics — including all the largest parties, which back the deterrent — argue that Trident underpins the UK's security and NATO commitments, and that abandoning it would be a historic strategic risk in a more dangerous world.

How it would work

Do not renew the nuclear-weapons system; cancel or wind down the replacement programme.
Pursue disarmament through international treaties and unilateral steps.
Redirect the savings toward conventional defence and public services.

The case for and against

Supporters argue

Trident is hugely expensive and the money could do more good elsewhere.
The UK could lead by example on disarmament and non-proliferation.
Nuclear weapons are of limited use against the threats the UK actually faces.

Critics argue

The deterrent is seen as central to UK and NATO security, especially amid rising global tension.
Unilateral disarmament could weaken the UK's position without others following.
Cancelling the programme would hit jobs and skills in the defence industry.

Sources & further reading

Green Party — the party's defence and Trident policy.
House of Commons Library — background on Trident and the Dreadnought programme.
Ministry of Defence — the UK's nuclear deterrent.

Figures are illustrative and based on reported proposals. General information, not financial, legal or tax advice.