Total retail sales volume, including automotive fuel, dropped by 0.9% month-on-month in August due to a fall in food sales.
Sales in food category declined 2.7% in August, offsetting the similar volume of increase in the previous month.
The agency noted that retail sales fell for the first time in four months and saw the largest drop since last October, while non food sales increased by 0.4% versus last month’s 0.3% drop.
Sales in household goods stores posted decline, which was 1.6% lower than in July.
Excluding automotive fuel, retail sales declined by 1% on a monthly basis after rising 1.2% in July. Year-over-year, retail sales, including automotive fuel, slowed unexpectedly to 2.1% from 3%.
Excluding auto fuel, sales increased 2.3%, which was slower than the 3.2% increase seen in July and the 3.2% growth forecast by economists.
Meanwhile, volume of non-store sector sales surged 28.7% annually and the value soared 28.1%, while the annual retail sales deflator dropped to 1.6% from 1.8% in July.
British Retail Consortium director general Helen Dickinson said while not quite on a par with an exceptional July, these are strong figures well above the annual average and are sustaining the positive momentum we’ve seen in recent months.
"August saw retailers preparing well for the shift towards Autumn and customers responded well to back-to-school offers as well as promotions on late summer stock."
"Alongside improving consumer confidence, a fourth month of shop price deflation and rosier news in the wider economy, this is further validation for the cautious optimism sensed by many at the moment," Dickinson added.