Last month’s riots in English cities had little impact on retail sales, which edged down 0.6% like-for-like during August.

Total sales advanced 1.5% over the month, the BRC-KPMG Retail Sales Monitor showed, although non-food categories continued to suffer during continued tough trading conditions.

BRC director-general Stephen Robertson said: “The riots were not widespread of prolonged enough to have a significant impact on these UK-wide figures.

“Poor consumer confidence, high inflation and the ongoing squeeze on personal finances remain the biggest threats to the retail sector.”

Food sales growth was similar in August to July, the BRC reported, but non-food sales were below their year-earlier level. Footwear suffered its worst sales fall since May 2009 and clothing sales were just below the level achieved a year ago. Homewares and furniture were both below their year-earlier levels.

KPMG head of retail Helen Dickinson said: “For non-food, the picture is disheartening with one of the worst monthly results of the year thus far - toiletries, cosmetics, and menswear the only sectors showing growth.

“The differential between food and non-food performance continues to grow with food sales in value terms remaining relatively resilient. 

“Given that much, if not all, of the growth is inflation and a higher VAT rate versus last year, this isn’t particularly good news for retailers as they struggle to maintain their margins.  

“Promotional activity remains high to drive footfall and interest which is a delicate balancing act for retailers to ensure the volume uplift compensates for the margin losses.” 

Online, telephone and mail order sales rose 12.6% in the month – the best performance since April.

On a weighted three-month basis food like-for-likes rose 1.4% and non-food fell 1.5%, giving a decline across all categories of 0.2%.