John Lewis brought the curtain down on a week of gloom for Britain’s shopkeepers on Friday with its worst sales performance this year.

Even the start of the department store chain’s summer sale last week was not enough to tempt shoppers as underlying sales fell more than 8 per cent in the week to June 28 and its electrical and homeware departments suffered double-digit declines. Sales at the chain, a bellwether for middle-class consumer confidence, have declined in recent weeks but last week’s fall is the most drastic and adds to evidence that the credit crunch is starting to affect even more affluent shoppers.