Government officials are stress-testing emergency contingency plans in the event of national power outage in Britain, according to a leak.
The secret plan - dubbed Programme Yarrow - warns that in a "reasonable worst-case scenario" multiple sectors could be "severely disrupted".
They include transport, food and water supply, communications and energy for up to seven days, according to The Guardian.
It was reported that in one worst-case scenario outlined by the blueprint only analogue FM radios would work and just BBC radio 2 and 4 broadcasting.
Exercises within Government and councils stress-testing the contingency plans have been held in recent days, it was claimed.
Last month experts warned that in the "unlikely" event of a shortage of gas this winter there could be planned three-hour blackouts to protect supplies.
But officials stressed that Programme Yarrow - drawn up in 2021 - pre-dates the invasion of Ukraine and outlooks published by the National Grid.
A Government spokesperson told The Mirror: "As a responsible government, it is right that we plan for all potential scenarios and work with the industry to prepare and exercise robust contingency plans.
"This work is ongoing continuously and is an important strand of our national resilience planning.
"Local and national exercises are a part of this ongoing work and ensure we are able to effectively respond to any wide range of scenarios, no matter how unlikely they may be."
But Labour's Shadow Business Secretary Ed Miliband said: "All governments do contingency planning for worst-case scenarios but the truth is that we are vulnerable as a country as a direct consequence of a decade of failed Conservative energy policy.
“Banning onshore wind, slashing investment in energy efficiency, stalling nuclear and closing gas storage have led to higher bills and reliance on gas imports, leaving us more exposed to the impact of Putin’s use of energy as a geopolitical weapon.”
