Preparations to transfer 10,000 civil and public servants and eight entire Departments out of Dublin in the country's biggest-ever decentralisation programme will begin in earnest this week.
The Decentralisation Implementation Group, chaired by industrial relations negotiator Mr Phil Flynn, will meet tomorrow, and it is expected to produce an outline plan for the three-year programme by the end of March.
Despite signs of disquiet by some senior officials, the Taoiseach, Mr Ahern, yesterday said: "I don't think that there is any great controversy about this, quite frankly."
Officials, he said, were "glad" the decision had been made.
"They know the blueprint, and, as always, they will get on with it. Of course there are some matters to be teased out. All of these things will happen."
He rejected charges that Departments could not be run effectively outside of Dublin. "
"With information technology and communications, some of the best companies in the world can now have board meetings with their parent companies in Australia, in Asia and the States.
"This happens every day. To be quite honest, it would be a bit of an insult to our own technology industry to think that we couldn't have good meetings from Kanturk to Athlone, or from Athlone to Portarlington."
However, he acknowledged the concerns of some officials.
"It is always a bit more difficult at senior levels because people are older, settled. People have their children in education, or their families are married. I understand that. That will work its way through though."
Meanwhile, both the Taoiseach and the Minister for Finance, Mr McCreevy, insisted that relocation expenses would not be paid.
"There never has been. And there won't be. To be frank, people moving out from the city will do very well. There are lots of gains," said Mr Ahern.
Mr McCreevy said officials quitting Dublin for other areas would "be making a fortune" by selling their Dublin homes and buying cheaper ones elsewhere.
Rejecting suggestions that the most senior civil servants would remain in Dublin, he said: "The Departments will be moving in total, the Minister, his secretary, the secretary general and all of the higher civil servants."
Speaking at the opening of the Kildare by-pass, Mr McCreevy said suggestions that the most senior policy-making officials would stay behind were "part of a Dublin mindset".
"Ireland is a small little country, and this is not rocket science. I don't put it on the same plane as putting a man on the moon, someone conquering the North Pole or even inventing the wheel. This is a quite sensible thing to do."
Dismissing critics who point out that most of the locations chosen do not feature on the National Spatial Strategy, he said: "The National Spatial Strategy and decentralisation are not the same thing. It was never ever linked to the National Spatial Strategy."
Union leaders representing civil and public service workers will meet with the Minister tomorrow.
One Civil and Public Service Union (CPSU) leader, Mr Blair Horan, said: "We won't know anything until we know how many people want to leave.
"If they get enough numbers, fair enough, then clearly they will not have to compensate anyone."
However, he laid down a marker that the Government will have to pay expenses to lower-grade staff if it finds that it is necessary to offer such inducements to higher ranks.
The Government's warning to civil servants not to oppose the changes has created deep unease amongst many of them, official sources have told The Irish Times.
"The Civil Service will always do what the government tells them, but the attitude now is that people can't even have different opinions," said one.
Many senior officials believe the transfer of eight Departments will badly hit public administration, and make the already-powerful Departments of the Taoiseach and Finance become even more influential.