What essentials should you keep ready as nations warn citizens to prepare for emergency?

Governments in the UK, the US, Japan, and across Europe are urging citizens to prepare for emergencies, with many advising people to keep essential supplies for at least 72 hours. An emergency kit should contain drinking water, non-perishable food, a battery-powered radio, a torch, a first-aid kit and essential medicines. It should also include blankets, a phone charger and cash.