While like-for-like food sales were up 1.4 per cent in the three months to August, compared to the same period last year, non-food sales dropped by 1.5 per cent on the same measure.
And August saw a sharper dip in activity on the high street, with like-for-like sales across all categories falling by 0.6 per cent annualised.
“The spell of hot weather at the start of the month was a boost for some retailers but it failed to last long enough to make a big impact,” said Stephen Robertson of the British Retail Consortium, which released the figures this morning.
“People had bought summer fashions early during the spring heatwave.”
Some good news for retailers came from internet sales, which were the strongest for four months in August.
Online sales are being boosted by bargain-hunters, Robertson added.
Sales of big-ticket items suffered and were “still often deal-driven”, as cash-strapped consumers sought out special offers.