Stormont's Department of Economy (DfE) has unveiled data quoted by DUP leader Sir Jeffrey Donaldson, in which he blamed rising food costs on the Protocol, which reveals the average cost of groceries is higher in Great Britain than in Northern Ireland.
It came after the DUP leader made claims around rising food costs in a BBC NI leaders’ debate on Tuesday night.
Sir Jeffrey said increasing food costs in Northern Ireland are "direct results of the NI Protocol” — and quoted data which was commissioned by a DUP led Stormont department and was not available to the public.
But DfE has now shared the Kantar grocery research, which they initially said they were not entitled to share as it was commissioned for a private report.
A spokesperson said: "Whilst there is nothing to suggest the Kantar GB Panel Average Price Tracker report has been shared with anyone outside of the Department it is clear that there is significant interest in some of the information contained within that report.
"The data are not official statistics, but they can provide some useful insight into the grocery market at an aggregate level. The panel size for NI is small & the NI figures are calculated from a sample of 650 households. GB figures are calculated from a sample of 30,000 households."
They went on: "The figures indicate that in December 2021 the average total grocery price in GB was 8% higher than in NI."
Some product categories in the tables used show the NI price is higher than in Great Britain.
"The average price per pack for dairy products in NI was 8% higher than in GB and the average price per pack for chilled convenience goods was 19% higher in NI," said the department's statement.
These statistics were quoted by Sir Jeffrey during the television debate, in which he said the price for dairy products has risen by 8% and by 19% for chilled convenience goods, something he said was a direct result of the Protocol.
He said: "As a direct result of the increased cost in bringing food products from Great Britain to Northern Ireland due to the Protocol, consumers in Northern Ireland are now paying on average 4% more per item than they are in Great Britain at the moment."
When asked earlier this week if Kantar states the price rises are directly linked to the Protocol, Mr Donaldson further told the BBC: “Yes, it demonstrates that the additional costs are linked to the increase in extra customs checks, delays in transporting goods, additional paperwork and additional staff that have to be employed [as a result of the Protocol.”