Energy regulator Ofgem has warned the country faces a "significant risk" of gas shortages over the winter.
Ofgem made the claim in a letter revealed by The Times.
The letter said there was a chance of a "gas supply emergency" because of the Russian war on Ukraine.
This war has already affected gas prices across Europe, and has led to energy prices rising.
A "gas supply emergency" is when energy firms cannot supply enough of the resource to meet demand.
It may mean businesses are asked to stop using gas for limited periods, in order to safeguard gas supplies to consumers.
The last time the UK had major organised blackouts was with electricity in the 1970s, with businesses rationing energy use and households told of when to expect power outages in newspapers.
Ofgem said it predicted “this winter to be more challenging than last year” and was taking “reasonable regulatory steps to mitigate and reduce the risks”.
Ofgem has been approached for comment.
The news comes as energy experts say Europe's gas supplies face “unprecedented risks” this winter.
The International Energy Agency (IEA) said. today that European countries would need to cut their gas use by 13% over the winter in case Russian gas supplies are completely cut off.
Russia has already cut off most of its gas pipelines to Europe.
Households may be asked to turn down their thermostats and boiler temperatures, while businesses will also have to save energy, the IEA said.
Energy bills have risen for millions of households as the £2,500 Energy Price Guarantee came into effect on October 1.
The new Government initiative replaces the Ofgem price cap - which would’ve seen bills rise to £3,549 for someone with typical use - and will be in place for two years.
It means households won’t face the hideous rises that were expected to come next year - with analysts previously predicting that gas and electricity bills will hit £6,000 in 2023.
But it still means the average home faces yearly energy bills of £2,500, with many homes paying even more.
Much like the old Ofgem price cap, what the Energy Price Guarantee will do is cap the unit rates you’re charged for gas and electricity, plus the standing charges.
This means if you use more energy, you could end up paying more than £2,500. Similarly, use less energy and your bill should be less.
The £400 energy discount is still happening and is on top of the £2,500 figure - so this takes the average yearly energy bill for someone with typical use to £2,100 a year.
