The Taoiseach Mr Ahern tonight said there was "huge concern" at government level about the spread of foot-and-mouth disease to Ireland.
He said: "It is really a national issue. If we were hit by a number of cases, it would be a real disaster.
"It's a £5 billion industry. We have an enormous animal population of around 20 million cattle, sheep and pigs.
"The danger for us from an economic point of view is the export market could be closed down and it takes a long time to gain the credibility of that market."
Mr Ahern was speaking before flying to London for talks on Northern Ireland - and foot-and-mouth issues - tonight with British Prime Minister Mr Tony Blair and to deliver an address to the Welsh Assembly tomorrow.
"In London I am just going straight to Downing Street and tomorrow I am confining my programme just to the Assembly and a nearby conference centre. I am dropping the remaining part of the programme and will comply totally with all of the disinfectant procedures - and I hope everyone else does, too," Mr Ahern said.
Mr Ahern also said he had heard of criticism about lax precautionary controls in response to the prospect of the disease reaching Ireland.
"We are trying to introduce disinfectant procedures at all points of entry to the country but that cannot be enforced without an enormous amount of cooperation from the public. That is why we are appealing to people the length and breadth of the island to cooperate in every way they can.
"We are endeavouring to ensure the procedures are as fail-safe as we can make them."
PA