Fact Sheet: Fissile Material Cutoff Treaty (FMCT)

A fissile material cutoff treaty would ban the production of fissile material for nuclear weapons purposes. Fissile materials, principally highly enriched uranium (HEU) and plutonium, are the essential ingredients for building nuclear weapons. The effective control and elimination of fissile materials is an essential step toward effective non-proliferation and a precondition for nuclear disarmament.

As of the beginning of 2022, the global stockpile of HEU is approximately 1,250 tons, which is a decrease of 190 tons from the 1,440-ton stockpile in 2011.This is enough HEU to make approximately 84,000 first-generation implosion bombs of the Nagasaki type. Approximately 88 percent of this HEU is available for or in weapons. Approximately 99.66 percent of the global stockpile of HEU is located in the nine nuclear weapon states, while the remaining .33 percent is located in Norway and Australia for civilian purposes. Russia owns 54.4 percent of global HEU, followed by the United States with 39 percent. HEU is often disposed of through downblending, which involves mixing HEU with natural uranium to produce low enriched uranium (LEU) to then be used for civilian purposes. The global stockpile of separated plutonium is 550 tons, 410 tons being produced outside of weapons programs under obligations not to be used in weapons and 140 tons available for or in weapons. Approximately 91 percent of the global stockpile of separated plutonium is owned by the nuclear weapon states, and the remaining 9 percent is owned by Japan and other non-nuclear weapon states. The United States estimates that as little as 4 kg of plutonium would be enough to make a weapon.

India and Pakistan (and possibly Israel and North Korea) are the only states that continue to produce fissile material for nuclear weapons. The United States, United Kingdom, Russia, and France have officially declared an end to their production for weapons. China has not been transparent about its fissile material production and was generally believed to have halted around 1990, but recent revelations, coupled with China’s obstruction of negotiation on a cutoff, have raised doubts.

Background

Treaty Aims and Challenges

In general, the nuclear weapon states prefer a treaty that bans only the production of new fissile material for weapons purposes and would not address pre-existing civilian fissile materials and weapons materials that have been declared excess for military use. India and Pakistan both continue to produce fissile materials for defense purposes. Doubts remain in Russia, the United States, and other countries about the efficacy, intrusiveness and cost of verification.

Non-Nuclear Weapon States generally view a FMCT as a step toward the elimination of nuclear weapons. They therefore desire a treaty that would prevent civilian stocks and stocks declared in excess for military use from being diverted for use in weapons.

Specific Country Perspectives

Verification

A verifiable treaty is important for numerous reasons. First, verification creates trust and builds confidence that the treaty’s requirements are being observed. Second, a verifiable FMCT could serve as a model for verifying the elimination of fissile material in the Nuclear Weapons States.

The IPFM assumes that verification of an FMCT that covers both future production and pre-existing stocks would be overseen by the IAEA Safeguards Division and cover uranium enrichment facilities, reprocessing facilities, material declared in excess for military use, and HEU for use in naval-propulsion reactor fuel. The Safeguards Division would have to expand greatly its operations to perform the intrusive activities necessary for verification. It would also require a larger budget, a cost that countries may be loath to incur.

Although arguments in the earlier stages of the FMCT supported verification be done by the IAEA Safeguards Division, other verification options have since been discussed. Some issues associated with oversight and verification by the IAEA Safeguards Division center around the technical and organizational factors. Existing safeguards would be replaced and strengthened data-collecting methods would be needed for former military fissile material production facilities, all the while still protecting classified information. To mitigate this, research has been done to explore the idea of establishing a standing verification group that would be part of the IAEA but still function independently from the Safeguards Division in terms of interacting with states parties, inspections, and conclusions, which would be passed to an independent FMCT organization to address compliance issues.

Since the start of FMCT ideas, new technology has advanced that could make other verification options possible. The IAEA installed the Online Enrichment Monitor (OLEM) to ensure that Iran kept enrichment levels no higher that 3.67 percent, which, in theory, could potentially be used as a verification method for the FMCT.

Although there seem to be other verification options since the earlier stages of the FMCT development, plans to use this technology for FMCT verification purposes have yet to come to fruition.