Ahead of Lisburn’s 148th Balmoral Show, Ms Truss highlighted in particular cross-border trade with the Republic of Ireland, which alone accounts for 65 per cent of all the food and drink exports from Northern Ireland.

Northern Ireland sends 83 per cent of its food and drink exports to the EU, compared to the UK average of 60 per cent. Meat exports account for over a quarter of this export value, at £280m, with dairy and eggs a close second at £240m.

Environment Secretary Elizabeth Truss said: "Family-run farms and innovative food and drink producers across Northern Ireland enjoy huge success in the EU, with over £1bn of produce exported there in 2015.

"Northern Ireland particularly benefits from easy, hassle-free trade with the Republic of Ireland - a vital source of income for farmers and food producers.

"If we were to leave the EU, Northern Ireland and the rest of the UK would not be able to negotiate a bilateral trade deal with the Republic of Ireland. Northern Ireland’s farmers would have no certainty on cross trade arrangements.

"Leaving the EU is a leap in the dark and a risk not worth taking, with no guarantees that such a good deal could be struck outside the EU. Northern Ireland’s world-class farmers and food producers are stronger, safer and better off in a reformed European Union."

During her visit to Northern Ireland the Environment Secretary met with Moy Park, the UK’s biggest poultry producer, which the Defra statement said was organised "to talk about the benefits of tariff-free access and common standards for food and farming businesses".