Labour has branded David Cameron "stuck-up" and "empty-headed" after he praised Waitrose for attracting the best grade of customer.
The Prime Minister gave his views on "supermarket sociology" as he visited a store run by parent company John Lewis in Cheadle, near Manchester.
"I have got a piece of supermarket sociology, which is that there is something about Waitrose customers ... they are the most talkative," Mr Cameron reportedly told staff yesterday.
"I found that if I shop in Waitrose it takes me about twice as long as everyone wants to stop you and have a chat. Whereas in other supermarkets I find I can dart round very quickly and get everything.
"It is something about your customers, they are very talkative, engaged people."
Mr Cameron revealed that he shops at Waitrose - regarded as a favourite of the middle classes - whenever possible. He uses Ocado - another firm catering to the higher end of the market - to deliver goods to Downing Street.
However, he said he went to Sainsbury's near his constituency home in Chipping Norton, Oxfordshire, "because there isn't a Waitrose".
The comments drew a personal attack from shadow Cabinet Office minister Michael Dugher.
"Families are on average £1,600 a year worse off since David Cameron became Prime Minister," he said.
"Most families understandably have to shop around and watch every penny because of the cost-of-living crisis, plus very many people increasingly have to rely on food banks.
"This is a world away from that of David Cameron.
"There's nothing wrong enjoying shopping at Waitrose. But Cameron seems to be saying that at Waitrose you get a better class of shopper.
"This is a bizarre and empty-headed intervention from a Prime Minister who increasingly gives the impression of being stuck-up and out of touch."