National Grid has warned it may not have enough gas to meet UK demand on Thursday due to the extreme weather conditions and supply issues.
It issued a "gas deficit warning" early on Thursday following "significant supply losses".
Shortages could affect industrial users as the Grid tries to balance supply and demand by buying in more gas if needed.
Despite the shortfall of about 50 million cubic metres, household gas supplies should not be affected.
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Why is demand for gas outstripping supply?
The biggest factor is the weather. The "beast from the east" is bringing sub-zero temperatures to the UK and with heavy snow, boosting demand for gas from both households and businesses.
The weather has also affected gas supplies. There have been problems with pipelines from Norway and the North Sea, and in recent days, problems with pipelines from the Netherlands and Belgium.
Energy analyst David Hunter of Schneider Electric said the industry used to have access to a major gas storage facility called Rough in the North Sea. However, Centrica closed the site, which was more than 30 years old, last year over safety issues.
This – together with other factors such as declining supplies from North Sea fields – means the UK is now more reliant on gas imports.
Demand for gas is also higher due to the increased of gas-fired power stations in the UK as coal-fired power stations are decommissioned.
On Thursday morning wind turbines accounted for the largest share of UK energy production, at about 26%, ahead of coal at 24%.
Will people still be able to use their gas central heating and cookers?
Yes. As energy analyst Peter Atherton says: "The last to get cut off is the domestic consumer."
If suppliers are not able to meet demand, certain users will be asked to stop using gas, he explains.
First gas-fired power stations will be asked to scale down gas use, followed by large industrial and business users.
A Department for Business spokesperson said "domestic households should not notice any disruption to their supply", with the gas deficit warning triggered to ensure supply meets demand.
A short-term increase in on-the-day wholesale prices is not likely to feed into household bills, the spokesperson added.
However, the cold snap has increased the number of requests for call-outs for engineers, British Gas said, which is having difficulty coping with the volume of customer queries.
Two of the company's call centres in Scotland have closed due to staff shortages following the cold weather.
How have companies been affected?
Chemical company Ineos told the BBC it is likely to cut gas usage at its Runcorn plant by a fifth in response to the National Grid's request.
However, the company said it did not expect the move to make a material difference as it gets most of the heat it needs from its own energy-from-waste plant.
There was a large spike in trading prices for gas bought on the day on Wednesday, but prices for gas bought a month ahead declined slightly.
Large energy suppliers mostly buy a month ahead so they can work out pricing for consumers and cut risks to their business.
However, they also buy a day ahead, as do large energy users, and smaller energy suppliers.