The shipping company Pandoro has won a Supreme Court battle allowing it to stop carrying live animal exports.
It means that Irish farmers are being left with no way to export live cattle out of the country.
The landmark ruling could cost farmers millions of euro.
Last year Pandoro exported over 100,000 live animals.
It has been claimed that no other shipping company has the capacity to export such large numbers.
ICMSA President Pat O'Rourke has said it will have a devastating impact on Irish agriculture.
He said: "In Ireland we are essentially land-locked as we are the only country in Europe who cannot export live animals. The issue must be addressed by the Minister for Agriculture."