Ministers have been accused of lecturing families on what to keep in their cupboards in case of a national emergency.
The Government is urging households to stockpile bottled water, tinned food, cash and loo roll in a campaign to be prepared for a potential major crisis caused by extreme weather or cyber attack.
Its Be Ready guide recommends keeping nine litres of drinking water per person in case mains supplies are knocked out or shops closed for as long as three days, along with meat, vegetables and fruit that can be eaten without being cooked or refrigerated.
Home survival kits should also include a battery or wind-up FM radio and torch, first aid kit and medication, the checklist says, while blankets are needed in case of power cuts.
In addition, the Be Ready advice includes working out escape routes from houses and agreeing with loved ones where to meet up in case disaster strikes, as well as filling in a form stating everything from insurance policy numbers to the frequencies of favourite radio stations.
Defence Secretary Wes Streeting said the public needed to think about what they would do if a natural disaster struck, if hackers attacked businesses or terrorists disrupted supply chains.
'How would we cope if the payment systems at the local supermarket went down?' he asked on a visit on Thursday.
'Those are the sorts of everyday challenges and threats that we could well face. And it's right that we ask the country to be ready for those things and to ask everyone to do their bit.'
Ministers have been accused of lecturing families on what to keep in their cupboards in case of a national emergency. Pictured: Andy Burnham
Security minister Dan Jarvis added: 'The storms last winter and the wildfires this summer have shown how severe weather events can cause disruption to our everyday lives and impact the services we rely on, like phones, power, water and the internet.'
But critics branded the advice over-the-top and said Labour should focus on keeping the country safe by raising funding for the Armed Forces, as well as improving the resilience of critical infrastructure such as power plants.
It comes after widespread anger at the Government sending emergency alerts to every mobile phone in the country during the summer to warn that lighting barbecues could spark wildfires.
Reform MP Danny Kruger, in charge of the party's preparations for government, said: 'Ministers should be doing their job not telling families how to do theirs.
Government needs to urgently invest in defence to deter aggressors and harden the target.
'With our undersea cables, our military bases and our civilian infrastructure all exposed to Russian or Iranian attack – and all our digital systems exposed to hackers from anywhere in the world – the need for a major uplift in defence spending at next week's Budget is critical.
'Meanwhile ordinary people need help with the cost of living – not bossy lectures about bottled water.'
Tory security spokesman Alicia Kearns said: 'Preparing for emergencies is important.
'But the Government should get its own house in order before lecturing the public. It isn't families that are failing to fund our defence or secure reliable energy, it's Labour.
'With rising threats to our national security, we must all be ready to face all eventualities.
'We each have a role to play, but the Government must lead by example.'
Lord Hannan, director general of the Institute of Economic Affairs, said: 'Britain is not a country on the brink of catastrophe, and ministers should not behave as though it were.
'The last thing we need is a Government encouraging people to panic. The purpose of government is to provide security and reassurance, not to frighten people into stockpiling tins of beans.'
And Dr Valentin Boboc, chief economist at the institute, added: 'There is nothing wrong with encouraging households to be prepared for emergencies, but the Government should be careful not to create unnecessary alarm.
'Talking up the prospect of a national crisis risks undermining consumer confidence at a time when households and businesses are already facing considerable economic uncertainty.
'Ministers should focus on ensuring that our infrastructure, energy supplies and public services are resilient.'
John O'Connell of the TaxPayers' Alliance said: 'Taxpayers want emergency warnings for actual threats, not money wasted lecturing them on common sense.'
The Be Ready website tells households: 'Being ready for three days helps you manage while support reaches those most in need.'
It advises: 'Check your cupboards first to see what essentials you already keep at home' and note down what is still needed.