Food sales grew by 4% but the BRC said this figure was "flattered by a smaller gain a year ago".

Director general Stephen Robertson highlighted the poor results in non-food retailing and said the benefit of warm summer and the World Cup had receded.

"The overriding factor is consumer confidence – it's fallen recently, though people are still more confident than this time last year. Talk of public sector spending cuts is unsettling consumers and they are concentrating on essentials," said Robertson.

Online and mail order sales showed the weakest growth for almost a year, although the value was still 11% higher than July 2009.

"Economic conditions are better than a year ago, but recent falls in consumer confidence reflect customers' mounting nervousness about making major spending commitments," said the BRC's Robertson.