Sales at John Lewis, the department store group, fell by nearly five per cent last week, ending a short recovery over the previous fortnight.

The department store put the 4.5 per cent drop in the week to July 26 down to hot weather keeping consumers away from the high street.

However, Howard Archer, chief UK and European economist at Global Insight, said the revenue bounce over the previous two weeks was a consequence of the department store's clearance sale and not a change in the softening trend.

Trading at John Lewis has declined in nine of the past 12 weekly surveys. Total sales for the week were £45.8 million - £2.1 million below the same week last year.

Home revenues fell 10.4 per cent, far steeper than the 5.3 per cent decline recorded in the same week of 2007. Fashion sales dropped 1.5 per cent and electricals and home technology reversed 1.7 per cent.

Stores at Glasgow, Southhampton, Peterborough, Cheadle and High Wycombe all recorded falls of more than 15 per cent.

While warmer weather impacted on total sales, trading in outdoor goods rose by 34 per cent.

Likewise at Waitrose, the high end supermarket chain owned by John Lewis, revenue was affected by the weather. Rising 3.8 per cent in total, Waitrose noted strong demand for salads, delicatessen, soft fruit, beers and barbecue products.

Mr Archer said consumer behaviour had fundamentally changed in 2008. "It is becoming ever more apparent that consumers are increasingly cutting back on their spending," he said.

"Many consumers are doing this out of necessity due to squeezed purchasing power, but it is also likely that many are retrenching out of choice reflecting serious concerns about the economic situation and outlook."

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