The UK has told people to fill their pantries with food for three days in case of catastrophe, joining a host of countries urging citizens to ready themselves for core systems failing.

Such advice, once dismissed as the preserve of preppers , has become more common in government circles as climate breakdown worsens weather extremes and geopolitical tensions turn cyber-attacks and sabotage into a regular occurrence.

Even in countries with national strategic food stockpiles – a buffer the UK lacks – authorities have asked individuals to play their part in societal resilience.

What actions do Britain’s allies – from the US and Europe to India and Australia – recommend people take before disaster strikes?

France

France calls the first 72 hours a “decisive period” in which people should monitor TV and radio news for official updates, and keep an emergency kit close by in case they have to get out fast.

In addition to the essentials, such as food, water, medicine and cash, the guidelines recommend filling…