Shop price inflation edged up to two per cent in March from 1.9 per cent in February – the fourth consecutive month of rising inflation.

The weakness of the pound was blamed for pushing up food costs but key general merchandise lines, such as clothing, were cheaper than a year ago.

Food inflation stood at nine per cent in March – the same as the previous month – the BRC-Nielsen Shop Price Index showed. Non-food prices fell 1.5 per cent compared to 1.7 per cent in February.

The BRC reported: “Overall inflation is being driven entirely by the food component, while the rate of non-food deflation has continued to fall since its peak in December 2008.”

BRC director-general Stephen Robertson said: “The shop price of food is increasing because retailers are paying more for their supplies.

“The majority of food consumed in the UK is sourced here, but the weak pound is pushing up prices for domestic produce as it becomes more attractive to overseas buyers and it’s increasing the cost of imports.”