FUTURE UK NUCLEAR WARHEAD CAPABILITY

This classified draft outlines the UK Ministry of Defence's evaluation of future nuclear warhead capability options as the country prepares for a long-term post-Trident era. The document assesses four main options (Base Case to Option 2 Plus), which represent increasing levels of technical capability, cost, and strategic assurance. The favoured Option 2 Plus includes re-manufacture of Trident physics packages mid-life, ongoing work on an alternative UK physics package, and sustained access to U.S. nuclear data under the 1958 Agreement. The paper also addresses supplementary options, including restoring UK independence in tritium production and reservoir filling, and maintaining minimal capability in warhead penetration aids to counter anti-ballistic missile systems. Costs and planning implications are detailed in annexes, including multi-year budget profiles. The Senior Nuclear Group and Chief of Defence Staff argue strongly that anything less than Option 2 Plus poses unacceptable risks to the credibility of the UK’s nuclear deterrent, especially without the ability to conduct underground nuclear tests. The paper concludes with a recommendation that the UK commit to Option 2 Plus and maintain independent tritium capabilities, with further planning to be considered in future long-term cost reviews.