UK retail sales grew by 4.5 per cent in value and 3.8 per cent in volume year on year during August. Food was one of the best performers, according to ONS data.
The growth in value of spending in predominantly food stores increased to 6.4 per cent, from 5.3 per cent in July.
Stronger sales in holiday-related trade - mainly food and drink - were attributed to the heatwave.
In the three months to the end of August, food sold well, growing 1.4 per cent by volume year on year.
The weakest performances were in clothing and non-store and repair operations - mainly mail order - noted broker CSFB.
Barclays retail director Richard Lowe said: 'August's figures were not only up on the previous month, but the underlying rate of growth was stronger than expected.'