Food inflation has hit a 15-month high rising to 4% in September, compared with 3.8% in August, British Retail Consortium (BRC) figures show.
Sharp rises in wheat, oil and corn prices contributed to the food price inflation.
Overall shop price inflation rose to 1.9% in September compared with 1.7% the month before, making it the highest level for five months.
However BRC director-general Stephen Robertson said that “past increases in commodity prices are now putting pressure on overall shop prices but the worst of this may have passed” as “weak demand, poor consumer confidence and strong competition between retailers” is likely to “hold back shop price inflation for the remainder of the year”.
Non-food inflation edged up 0.7%, driven by a rise in cotton prices, which affected the cost of clothing.
Robertson said that clothing is “still cheaper than a year ago, and 15% cheaper than five years ago, but rising cotton costs have slowed the pace of those price falls”.
In September, annual deflation in the furniture and floorcoverings category was 0.2% - less than the 0.5% in August.
Deflation in the electricals category slowed to 2.6%, from 2.8% in August.
Inflation in the DIY, gardening and hardware category remained at 3.7% for the second consecutive month.