Pages 72-73 from FCO 177-552

This document discusses the production and supply of low-enriched uranium (LEU) and weapons-grade plutonium for the UK's nuclear programs. LEU, which has a relatively low uranium-235 content, is produced under a contract that expires in 1996. The US provides LEU to the UK for enrichment, and in return, the UK sends an equivalent quantity of highly enriched uranium (HEU) from its stockpile.

The US has confirmed that they considered the UK's future requirements when assessing the adequacy of their stockpile before deciding to halt fissile material production. However, substantial quantities of HEU are still needed for the Trident program and the nuclear submarine fleet. The replacement for the HEU-powered HEU is expected to come from warheads withdrawn from service.

Weapons-grade plutonium is produced for the Trident program in Calder Hall Mognox reactors at Sellafield under a contract with BNFL. The recovery of plutonium from retired weapons is expected to meet the UK's foreseeable needs. There are plans to produce additional material, and terminating the contract with BNFL would be as expensive as continuing it. The UK believes that the US does not have available plutonium that meets its needs, nor the operational facilities to convert it to a suitable form.

The document also mentions that the UK's reliance on US support for intelligence on Russian activities is not dependent on UK equipment or assets. The UK's ability to assess and respond to Russian activities is not compromised by relying on US intelligence.

Overall, the document provides information on the UK's nuclear material production and supply arrangements, as well as its reliance on the US for intelligence on Russian activities.