For most of the last 15 years, around 50% of all lambs produced in Northern Ireland went to the Republic of Ireland for direct slaughter. Given the extent of the trade, it has been the major driver of prices. In general, local factory buyers tend to match the prices paid by southern buyers in NI marts and not the other way around.Therefore, any upset to the export market south is a major issue for the sheep industry in NI. The problem is caused by new country-of-origin labelling rules on lamb, pork and poultry, which mean that packaged meat products must now indicate the country where an animal was reared, as well as where it was slaughtered and processed.