An Asda supermarket displays bell peppers in south London on Jan. 10. (Justin Tallis/AFP/Getty Images)

Early last year, KFC stores in Britain ran out of what fried chicken connoisseurs might consider a critical ingredient: chicken.

As the chain grappled with an unexpected issue with its chicken supplier, hundreds of KFC branches in Britain temporarily shut down. “A chicken restaurant without any chicken,” said an advertisement the chain took out in British newspapers to apologize for the mishap. “It’s not ideal.”

Now the chain is warning that a no-deal Brexit could lead to plenty of new shortages.

KFC, McDonald’s and Pret a Manger, along with a number of major British supermarkets, signed a letter sent to British lawmakers this week warning about the risk to Britain’s food supplies if the country leaves the European Union on March 29 without having reached a deal on withdrawal terms.

The companies wrote that nearly a third of food consumed in Britain comes from elsewhere in the E.U. In March, when produce is out of season in Britain, “90 percent of our lettuces, 80 percent of our tomatoes and 70 percent of our soft fruit is sourced from the EU,” the letter read.

The companies also warned that stockpiling can only help to a certain degree, since “all frozen and chilled storage is already being used and there is very little general warehousing space available.” And fresh food, of course, is hard to stockpile at all. Grocery stores would probably become empty and prices for goods could soar.

“We are extremely concerned that our customers will be among the first to experience the realities of a no deal Brexit,” the letter said.

The British government has played down concerns over such shortages. A spokesman for the government told CNN this week that Britain has a “high level of food security built upon a diverse range of sources including strong domestic production and imports.”

But the fear among some Brits is real: Some have been aggressively stockpiling supplies, from dry food and water to toilet paper and wine. There are even food kits for sale intended to last for 30 days.

Others are skeptical that there would be any disruptions at all. One man interviewed by BBC News this week said it was “purely scaremongering.” He then suggested that if Britain did run out of food, it would “do the country good.”

“Make them appreciate what they’ve had,” the bespectacled man said.

That declaration got quite a response on British social media.

“Going without food will make us appreciate what we had. Which, to be clear, was food,” one Twitter user wrote.

“It’s scary to think these folk walk among us,” said another.

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