AS UK taxpayers prepare to fork out millions of pounds for lifeline supplies of gas, drinks bosses in Northern Ireland have revealed they are unaffected by desperate shortages in Britain – due to the Brexit deal signed by Boris Johnson.

A deal brokered by Business Secretary Kwasi Kwarteng will see the UK Government provide "limited financial support” for CF Fertilisers, a major US-owned manufacturer, to prevent a food supply shortage in Britain's supermarkets.

The agreement will be in place for three weeks while the "CO2 market adapts" to the surge in global gas prices, according to the Department for Business, Energy and Industrial Strategy (Beis).

Environment, Food and Rural Affairs Secretary George Eustice said the final details of the agreement were still being worked on but "it's going to be into many millions, possibly the tens of millions".

CF Fertilisers suspended production at plants in Teesside and Cheshire due to soaring energy costs as global gas prices spiked.

The CO2 produced as a by-product at the plants is vital to the food industry, where it is used to stun animals in slaughterhouses, keep packaged products fresh and make fizzy drinks.

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The British Soft Drinks Association has warned manufacturers have “only a few days” of CO2 left to produce fizzy drinks. It said that, due to Brexit restrictions, producers cannot import supplies of CO2 from the EU.

"Relying on European supply is not feasible given the problems associated with Brexit and the fact that CO2 production on the continent is also disrupted," the organisation stated.

AG Barr, which makes Irn-Bru, Rubicon and Tizer, has warned of the potential impact to their supplies.

The company said it currently has reasonable access to gas as it has invested in CO2 storage over the years – but is concerned about what comes next.

“We're currently producing to normal schedules however if the situation worsens across Europe then we could be impacted, but we're taking action to protect normal customer supply as much as possible,” the firm told The Scotsman. “We have worked hard to build resilience into our CO2 supply chain over a number of years however these are quite unprecedented circumstances.”

The National: File photo dated 9/9/2011 of bottles of Irn Bru in the production hall at AG Barr's Irn Bru factory in Cumbernauld. The Scottish drinks company has said it is seeing encouraging trading as people return to restaurants, pubs and bars around the UK.

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But it’s a different story in Northern Ireland, which remains in the single market thanks to the UK Government’s Brexit protocol.

Coca-Cola, which employs more than 500 staff at its facility Lisburn, said it has plentiful supplies of CO2.

In a statement to BBC News NI, the company said: "Coca-Cola HBC Ireland and Northern Ireland is not experiencing any risks to its CO2 supply.

"We also have robust contingency measures in place and do not expect any disruption to production."

Despite agreeing to the Northern Ireland Protocol as part of the Brexit negotiations with the EU, the mechanism has been heavily criticised by senior Tories.

Brexit minister Lord Frost claimed earlier this year that is “isn’t sustainable in the way it’s working”.

Earlier, Eustice defended the decision to pump tax money into CF Fertilisers.

"The truth is, if we did not act, then by this weekend, or certainly by the early part of next week, some of the poultry processing plants would need to close, and then we would have animal welfare issues - because you would have lots of chickens on farms that couldn't be slaughtered on time and would have to be euthanised on farms. We would have a similar situation with pigs," he told Sky News.

"There would have been a real animal welfare challenge here and a big disruption to the food supply chain, so we felt we needed to act."

It was "justified for the Government to intervene in this way, in a very short-term, targeted way" because "if we didn't, there would be a risk to our food supply chain - that's not a risk the Government is willing to take", he told BBC Radio 4's Today programme.

Kwarteng said the decision would avert disruption in the "many critical industries that rely on a stable supply" of carbon dioxide.

CF Fertilisers produces around 60% of the UK's CO2, used primarily by the food sector but also in the health and nuclear industries. It suspended operations at its Teesside and Cheshire plants because of high global gas costs.

Beis officials said the "exceptional short-term arrangement" with the American business would allow the company to immediately restart operations and produce CO2 at its Billingham plant in Teesside.

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Eustice suggested the second plant would also be brought back online.

He said the food industry will have to accept a major hike in C02 rates, which could increase fivefold from £200 a tonne to £1000, but because the gas makes up only a small part of overall costs there would not be a "major impact on food prices" for consumers.

Ian Wright, chief executive of the Food and Drink Federation, said: "I think it's a temporary solution but it's a welcome one, and means there won't be many noticeable shortages on the shelves, although there are already some because of staff shortages."

He said the industry needs to "get its act together".

Wright also warned that although food would continue to enter warehouses in the lead-up to Christmas, "the supply chain is so fragile that any other shock might do it in as well".

Eustice told LBC Radio "Christmas is safe" but acknowledged "there are challenges in the food supply chain".

The shutdown of CF Fertilisers' plants coincided with maintenance at two other factories which supply CO2 to the UK.