The Government is awaiting the results of foot-and-mouth tests on sheep from a farm in Co Louth.
The samples taken from the sheep are being processed in Britain at the only authorised testing facilities in these islands.
The Department for Agriculture is expected to announce even tighter controls on the movement of animals today which are expected to prohibit the movement of animals to abattoirs or meat plants without a permit.
The Government is also revising legislation dealing with the movement of animals in the Republic and the role of dealers, the Taoiseach said yesterday.
Mr Ahern said the legislation is in the process of being update but this will be revised in the light of recent developments. He urged caution in the views expressed on the threat from foot-and-mouth disease.
Department of Agriculture officials have traced 72 sheep which came in from Britain, using information supplied by a dealer who has been questioned by British police about the illegal importation of sheep.
This led to the immediate slaughter of nearly 300 animals on a Co Louth farm and an investigation at the Kildare Chilling Plant, where sheep from the same flock had been processed. It has been closed down pending the investigation.
Tissue samples have been sent to the laboratory in Britain for analysis. If the samples are positive, the results will be known later today. But, it will take a further 48 hours to verify a negative result.
Along the border the build-up of troops from the Defence Forces continues. There are now 4,000 personnel in place to assist in the efforts to prevent the spread of the disease into the Republic.
It has been reported the North's Chief Veterinary Officer, Mr Bob McCracken has said the results of the tests of suspected animals in Castlederg have shown negative.
In the North, about a 1,000 pigs have been slaughtered as precautionary measure on a farm in South Armagh.
According to reports the incineration took place on a farm within the exclusion zone close to the farm at Meigh, on the Armagh-Louth border where the North's only case of foot-and-mouth has been confirmed.
