Potato value sales have fallen for the first time since early 2012, as a huge spike in promotional activity has weighed down prices.

According to the Potato Council, which cited Kantar Worldpanel data for the 12 weeks to 20 July, 40% of all fresh potatoes were sold on deal compared with 14% a year ago. This contributed to average prices falling by 9.9% and value by 12.3% over the period.

On a 52-week basis, value sales for fresh potatoes fell 1.9% to £1.3bn. Volumes were down 6.8% for the same period.

“There has been a large exodus of buyers from the value potato category, possibly linked to a reduction in value lines in some of the major multiples,” it said.