Former chiefs of Tesco, Sainsbury’s, Marks & Spencer and B&Q issued a blunt warning against cutting ties with the EU last night.
They said a vote to quit the bloc in next month’s historic referendum would cause shop prices to rocket – a claim backed up by Cameron.
And they dismissed suggestions by top Brexit campaigners including Boris Johnson that Brussels red tape holds back businesses.
They wrote: “We believe an exit could be catastrophic for the consumer recovery on which so much of our economic stability depends.
The unintended consequences of a Leave vote and the uncertainty it would create would be a massive shock to the system.
“It would probably mean further depreciation of the pound, driving up the price of imported goods for consumers.”
intervention by Sir Terry Leahy, Marc Bolland, Justin King and Sir Ian Cheshire.
He said: “This is a stark warning from our most successful retailers about the risks Britain faces if we leave the EU.
“They are absolutely clear that millions of families will face higher prices in the shops.”
But a spokesman for Vote Leave dismissed the letter, telling the Mail: “The EU is good for the bosses and for the bankers.
“It isn’t good for the public who have to pay the taxes that go to the EU instead of to our NHS and it isn’t good for small businesses.
“As independent experts have found, the EU pushes up the prices in our supermarkets because of its protectionist policies.”