Last month's heatwave, coupled perhaps with a pause for breath after two free-spending months before and during the World Cup, retail sales went into reverse last month for the first time since January.

Overall, the volume of sales fell back by 0.3 per cent between June and July, even after the growth in June was revised down to 0.7 per cent from a 0.9 per cent increase first reported. But July's sales were still 0.4 per cent above those in July last year.

The biggest single factor last month was a 3.4 per cent drop in sales of household goods.

Non-store retailing - including Internet shopping as well as mail order - also fell, by 2.6 per cent.

Taking the latest three months together, National Statistics still described the trend as "robust" compared with the growth over the last two years.

Birmingham Chamber of Commerce and Industry took a very different view - that the setback proved that the Bank of England acted prematurely when it raised interest rates last month.

"We warned that the improvement in UK output seen during the second quarter of the year was as a result of the boom caused by the World Cup," said James Cooper, the Chamber's policy adviser.

"We are now seeing a resumption of normal service."

Unemployment, he added, has risen again and is now 0.7 per cent higher than last year.

"The reality is that the economy is, while performing reasonably, still in a fragile state."

Tim Sleep, director of retail at Ernst & Young, highlighted the patchy nature of the sales numbers.

"The hottest July on record kept the hordes of shoppers away," he noted. "DIY in particular was hit hard by the heatwave, but sunshine boosted sales of food, drink and outdoor gear.

"Elsewhere, electricals, which had enjoyed strong sales in the run up to the World Cup, returned to more normal levels.

"Alongside this, summer discounting continued to play its part in driving sales volumes. Retailers may be shifting their end of season stock, but, as ever, at the expense of profit margins."

While Mr Cooper called on the Bank not to raise interest rates again next month, Mr Sleep expects the next move to be upwards.

"Add in the prospect of much increased energy bills this winter facing both retailers and consumers and throw in the impact of the renewed terrorist threat - that could severely dent tourist spending - it is clear that the retail sector outlook is far from rosy."

Clothing sales did well in July, but NS said this reflected steep discounting. Prices overall were on average 0.5 per cent lower than a year earlier.

Howard Archer, an economist at Global Insight, argued that more subdued retail sales could persuade the Bank to defer any move to raise interest rates.

"Much attention will now be focused on how well retail sales fare following the interest rate hike," he said.

"While record high employment will provide some support, we believe that consumer spending is likely to be muted over the coming months."

In view of that, "the Bank of England may well hold off from any further interest rate increase until next year".