The Industrial Development Authority's warning that a second rejection of the Nice Treaty could threaten foreign investment and jobs in the Republic has sparked a major political row.
Both the Tánaiste, Ms Harney and Fine Gael's Mr Gay Mitchell defended the IDA chief executive, Mr Sean Dorgan in the face of strong attacks from the Green Party and Sinn Féin.
Meanwhile, the Referendum Commission will have €3.5 million to spend on a public information campaign on the Nice Treaty before the poll in October.
The chairman of the Green Party, Mr John Gormley, said Mr Dorgan's warning was "blatant political interference" in a sensitive political matter.
"His warning that a No vote could have consequences for investment echoes the Government's scaremongering tactics, but has no basis in fact. If Mr Dorgan could point to one investment decision that has been affected by the Irish No vote last year, he should say so," he said.
The Sinn Féin Dublin TD, Mr Aengus Ó Snodaigh accused the IDA of "crass intervention" and "as a mouthpiece for the Government campaign".
Ms Harney responded vigorously: "This is a cheap political attack on a man working to bring jobs into Ireland. If Sean Dorgan believes that Ireland's relationship with European is crucial to bringing foreign investment into Ireland, then he is absolutely right to say so.
"The IDA is recognised as one of the most professional investment agencies in the world and it does no good for Ireland if political parties try to score cheap points in this way. The IDA knows more about job creation in Ireland than the Green Party and Sinn Féin put together," she said.
The newly appointed chairman of the Oireachtas Committee on European Affairs, Fine Gael TD, Mr Gay Mitchell defended Mr Dorgan's comments, and his right to voice them.
"If he believes that there are consequences then he not only has the right to make that known, he has the duty to do so," said Fine Gael TD Mr Gay Mitchell. The new Oireachtas committee he chairs is to vet all EU measures before they are agreed in Brussels.
"The sceptical British have signed up for Nice. Are we somehow trying to be even more sceptical than they are? If so, then there is a danger that a second "No" vote could translate into a jobs haemorrhage," he said.
An order establishing the Referendum Commission chaired by the former Chief Justice, Mr Tom Finlay, was signed yesterday.
The other members of the commission are the Comptroller and Auditor General, Mr John Purcell; the Ombudsman, Mr Kevin Murphy; the Clerk of the Dáil, Mr Kieran Coughlan; and the Clerk of the Seanad, Ms Deirdre Lane.
The commission will be able to plan its information campaign although the Oireachtas is not due to pass the legislation for the referendum until mid-September.
The timing means the commission will "have the time and support they need to execute their responsibilities and offers greater opportunity for enhanced debate and discussion among the voters on the issue of Nice," the Minister for the Environment, Mr Cullen, said yesterday.
In a report to the Government last year Mr Finlay complained strongly that the Referendum Commission had been given too little time to explain the issues behind the first Nice Treaty poll.
Following changes to the Referendum Act last year, the commission will produce a general explanation of the treaty - but it no longer has responsibility to put both sides of the argument.
"The Nice Treaty is of great significance to Ireland and the part we wish to play in Europe. I am confident that the information provided by the commission will increase public awareness, which will result in the electorate being in a position to make an informed decision at the forthcoming referendum and express that decision by coming out on polling day to cast their votes," Mr Cullen said.
