* CO2 shortage is caused by closure of fertiliser plants
* Meat industry needs CO2 for animal slaughter, packaging
* Ocado reduces lines of frozen foods it can deliver (Adds Ocado, Cranswick, updated BRC line, farmers union)
By James Davey
LONDON, Sept 20 (Reuters) - Some of Britain's meat processors will run out of carbon dioxide (CO2) within five days, forcing them to halt production and impacting supplies to food retailers, the head of the industry's lobby group warned on Monday.
A jump in gas prices has forced several domestic energy suppliers out of business and has shut fertiliser plants that also make CO2 as a by-product of their production process.
The CO2 gas is used to stun animals before slaughter, in the vacuum packing of food products to extend their shelf life, and to put the fizz into beer, cider and soft drinks. CO2's solid form is dry ice, which is used in food deliveries.
The CO2 crisis has compounded an acute shortage of truck drivers in the UK, which has been blamed on the impact of COVID-19 and Brexit.
"My members are saying anything between five, 10 and 15 days supply (remain)," Nick Allen of the British Meat Processors Association told Sky News.
With no CO2 a meat processor cannot operate, he said.
"The animals have to stay on farm. They'll cause farmers on the farm huge animal welfare problems and British pork and British poultry will disappear off the shelves," Allen said.
"We're two weeks away from seeing some real impacts on the shelves," he said, adding that poultry could start disappearing even sooner.
Allen said the government was working hard to try and resolve the issue and might be able to persuade a UK fertiliser producer to re-start its plant.
The crisis is also having a more immediate impact.
Online supermarket group Ocado said it had temporarily reduced the number of lines it is able to deliver from its frozen range. Dry ice is used to keep items frozen during delivery. Ocado shares were down 2.7% at 1105 GMT.
Shares in processor Cranswick, whose products include fresh pork and chicken and gourmet sausages, were down 2.7% after CEO Adam Couch said production could be halted.
The British Retail Consortium (BRC), which represents retailers including the major supermarket groups, said the CO2 shortage had compounded existing pressures on production and distribution.
"... it is vital that government takes immediate action to prioritise suppliers and avoid significant disruption to food supplies," said Andrew Opie, the BRC's director of food and sustainability.
Britain's National Farmers Union said it was concerned about the shortages of fertiliser and CO2.
"We're aware of the added strain this puts on a food supply chain already under significant pressure due to lack of labour," said NFU vice president Tom Bradshaw.
Foreign office minister James Cleverly said the government was looking to address short-term shortages.
"We will ensure that we are able to put food on the table, obviously that is a real priority," he told Sky News.
Britain's big four supermarket groups - market leader Tesco , Sainsbury's, Asda and Morrisons - had no immediate comment. (Reporting by James Davey; editing by Guy Faulconbridge, Jason Neely and Gareth Jones)
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