Greater transparency on sheep imports has been demanded by farmers following recent confusion around the number of stock brought into the country for slaughter.
ICSA sheep chair Sean McNamara said Agriculture Minister Barry Cowen needed to address the issue "as a matter of urgency".
While figures from the EU's Trade Control and Expert System supplied by the Department of Agriculture show that Ireland imported 521,798 sheep in 2018 and 461,522 in 2019, the corresponding figures from the CSO were just 19,232 and 19,305.
The CSO said it was investigating the significant differences between the two data sets.
"There may be valid reasons for this, related to below-threshold trade, and whether or not there has been a change of ownership when meat processing plants process the meat; but as of yet, we do not have a definitive answer," a CSO official stated.
Meanwhile, Northern Ireland's Livestock and Meat Commission confirmed that 421,365 sheep from Northern flocks were exported to the Republic in 2018, with the figure for 2019 totalling 380,431. As the Northern Irish export figures are around 100,000 and 80,000 head respectively below total imports into the Republic for 2018 and 2019, it is accepted in the industry that imports directly from Britain make up the difference.
The ICSA is calling on the Department of Agriculture to provide:
■ Weekly reports on the number of lambs imported, and from where;
■ Full transparency around which markets these imported lambs are servicing;
■ A comprehensive explanation on how farmers can be assured these lambs are not being sold as Origin Green lambs;
■ An outline of the veterinary protocols and traceability requirements on all lambs at the point of export before they come to Irish meat factories.
A spokesman for Meat Industry Ireland insisted that all live sheep imports were "as per EU legislation" and their carcases and resulting product were "labelled in accordance with EU labelling legislation".