Leading British supermarkets and food service chains have warned that a no-deal Brexit will lead to higher prices and empty shelves in the short-term.

The British Retail Consortium (BRC) made its latest warning in a letter sent to lawmakers. It was also signed by the bosses of supermarket groups Sainsbury's, Asda, Waitrose and Lidl and fast food chains McDonald's, and KFC. 

The U.K. is currently due to leave the European Union on March 29, but Parliament two weeks ago voted heavily against a deal reached by Prime Minister Theresa May regarding the country's future relationship for when it leaves the economic bloc.

If the country leaves the EU without a deal, many laws in place governing trade would cease to apply, and experts have warned that there would be widespread disruptions.

In the letter, the groups say there will be "significant risks" to maintaining the choice, quality and shelf life of food.

“While we have been working closely with our suppliers on contingency plans it is not possible to mitigate all the risks to our supply chains and we fear significant disruption in the short term as a result if there is no Brexit deal,” the letter said.

“We are therefore asking you to work with your colleagues in Parliament urgently to find a solution that avoids the shock of a no-deal Brexit on 29 March and removes these risks for UK consumers.”

The letter noted that nearly one-third of the food eaten in the U.K. comes from the EU. The situation would be even more acute in March when British produce is out of season, with 90% of lettuces, 80% of tomatoes and 70% of soft fruit sourced from the EU at that time of year.

“As this produce is fresh and perishable, it needs to be moved quickly from farms to our stores,” it said. “This complex, ‘just in time’ supply chain will be significantly disrupted in the event of no deal.”

The BRC noted that even if the British government does not undertake checks on products at the border, there will still be major disruption at Calais as the French government has said it will enforce sanitary and customs checks on exports from the EU.