The European Union is likely to ban the import of beef from Argentina, following an outbreak of foot-and-mouth disease in the Corrientes region close to the Brazilian and Paraguayan borders.
Argentina is the third-largest beef exporter in the world and has been making serious inroads into European markets and displacing locally produced beef in recent years.
An Bord Bia, the Irish Food Board, said it was expected that imports of beef from the infected region will be suspended.
In 2005 Argentina exported a total 154,000 tonnes of beef to the EU.
Russia takes large supplies of beef from Argentina, and it has been in direct competition with Irish beef on the Russian market.
Russia is likely to follow Chile and Uruguay, which have already banned imports of beef from Argentina.
Last year Argentinian exports were worth nearly $1.4 billion, but the discovery of 70 infected cattle on a ranch in the region is likely to bring a partial ban on exports.
Mr Jorge Dillon, director of animal health in Argentina, told reporters the government will slaughter 3,067 cattle that could have been infected on the same ranch.
Brazil, which had two outbreaks of the disease last year, is still banned from exporting beef to the EU from the affected region.
The Irish Farmers' Association called for a complete ban on imports from South America, where it said border controls were inadequate and animal traceability was non-existent.
The Irish Cattle and Sheepowners' Association also called on consumers to buy only Irish beef, to ensure that foot-and-mouth would not be brought into this country.