IN Brief:
- The NAO says the food system's ability to withstand catastrophic disruption has not been tested.
- Food businesses had limited involvement in recent national exercises and Defra's disruption playbook.
- Greater infrastructure mapping, industry engagement, and cross-government planning could strengthen preparedness.
The UK’s food supply chain has proved capable of absorbing recent disruption, but its ability to withstand a catastrophic event has not been properly tested, according to the National Audit Office. The watchdog says government has relied heavily on private-sector resilience while risks including extreme weather, cyber-attacks, energy failure, and disease become more severe and interconnected.
Food is one of the UK’s 13 Critical National Infrastructure sectors, spanning agriculture, manufacturing, storage, distribution, wholesale, retail, and catering. Its resilience therefore depends on far more than food production itself. Electricity, fuel, transport, warehouses, cold stores, communications, labour, data systems, and specialist industrial inputs all have to remain available if product is to continue moving through the chain.
The system has performed comparatively well during substantial recent shocks. Private businesses kept food moving through the COVID-19 pandemic and the disruption following Russia’s invasion of Ukraine in most cases without extensive direct government intervention. Defra has consequently been able to rely on commercial incentives encouraging companies to maintain contingency plans, diversify supply, hold appropriate stocks, and respond when normal sourcing or logistics are interrupted.
The NAO’s concern is that resilience demonstrated during one type of disruption does not establish that the system can absorb a larger or fundamentally different event. The National Risk Register includes low-probability scenarios capable of causing catastrophic food shortages, including a nationwide power outage, another pandemic, a nuclear accident, or a large-scale chemical, biological, radiological, or nuclear incident.
Those scenarios differ from a conventional supply interruption because several dependencies could fail at once. A prolonged power outage, for example, would affect refrigeration, automated warehouses, food-processing lines, communications, fuel distribution, and payment systems simultaneously. Severe weather can obstruct roads and ports while also affecting production, while a cyber incident can disable ordering, inventory, transport-management, or warehouse systems even where physical goods remain available.
Government exercises have not yet provided a comprehensive test of how those failures would interact. The last national exercise addressing catastrophic food disruption took place in 2023, and food supply chain businesses were largely excluded. Companies also told the NAO that they had limited input into Defra’s food disruption playbook.
That gap is operationally significant because much of any emergency response would still depend on the private companies that own warehouses, vehicles, processing plants, distribution centres, and stock. Plans developed without the organisations expected to execute large parts of them risk overlooking practical constraints around labour, fleet availability, site access, refrigeration, replenishment, and communications.
Local coordination presents another weakness. England’s 38 local resilience forums are responsible for planning for emergencies in their areas, but some have reported insufficient clarity over what Defra would expect during a major food supply disruption. The NAO also identified wider concerns over cross-government coordination and uncertainty around whether the department has every legal power it could need during a catastrophic event.
Critical infrastructure mapping is therefore more than an administrative exercise. The NAO says government could make better use of the Critical National Infrastructure Knowledge Base to identify strategically important food assets and dependencies. Warehouses, distribution routes, processing facilities, utilities, and other nodes can have consequences far beyond their immediate location when relatively few alternatives exist.
Industrial inputs can create similar concentrations. Government is separately examining the resilience of food and medical-grade carbon dioxide supply after repeated market failures in 2018, 2021, and 2026 required intervention. Food-grade CO2 supports processing, packaging, chilling, and other operations, yet domestic availability can depend on production elsewhere in the chemicals and fertiliser sectors.
There is also a commercial limit to the redundancy businesses will carry without a clearer view of the disruption government expects them to withstand. Extra inventory, duplicate distribution capacity, alternative suppliers, emergency power, additional transport contracts, and redundant IT systems all impose costs in normal conditions. The NAO therefore argues that Defra needs to be clearer about acceptable risk and whether further resilience measures represent value for government, industry, and households.
Its recommendations include renewed engagement with food supply chain companies, testing response plans with industry and local government, assessing approaches used by other countries and CNI sectors, and reviewing the legal powers available during catastrophic disruption. Defra has expanded its Food Supply Chain Resilience team and increased attention on severe scenarios, but the NAO considers that work to remain at an early stage.
The report does not argue that Britain’s food supply chain is routinely fragile; recent disruptions have repeatedly shown considerable commercial adaptability. The unresolved weakness is that government and industry have not yet demonstrated how that adaptability performs when several critical dependencies fail together. Until such a scenario is tested jointly, preparedness rests heavily on assumptions derived from less severe shocks.
