The proposed rail link between Dublin Airport and the city centre is to be abstracted from the wider metro plan so that it can be delivered by 2007, the Minister for Transport, Mr Brennan, announced yesterday.
He also suggested that the rail link "won't necessarily be underground", saying he had asked the Railway Procurement Agency to identify "the speediest, cheapest, quickest option" for serving the airport.
Asked whether this might mean a new rail spur off the Maynooth line, as proposed by an Aer Rianta-Iarnród Éireann working party in 1999, a spokesman said the Minister was "thinking out loud" on the issue.
Mr Brennan was reacting to a report in The Irish Times yesterday that a feasibility study had found that a metro link from St Stephen's Green to the airport would take over eight years to deliver and cost billions more than anticipated.
He said the quoted figure of €20 billion related to the entire metro plan and, in any case, was "not accurate". The figure for the airport link, which would now become a "separate project", was around €2 billion.
"The metro is not going to run over-time. The Government decided that the section from the airport to the city centre would be extracted from the main metro plan and put together as a separate project."
Pledging that the airport link would be ready by 2007, the Minister said it would be funded by a public-private partnership, with contributions from Aer Rianta and the proposed new air terminal.
As for the rest of the metro plan envisaged by the Dublin Transportation Office strategy, he agreed it was almost certain it would take 10 years to implement "and the funding is not yet identified for it".
Mr Frank Allen, the RPA's new chief executive, said it was premature to speculate that the metro would cost €20 billion over a 20-year period because different options were still being examined by the agency.
The Dublin Chamber of Commerce said the metro plan "must go ahead" and there should be no significant delays or cost overruns providing there was a firm Government commitment to deliver it.
The chamber's policy director, Mr Declan Martin, said the metro was an integral part of the Dublin Transportation Office's Platform for Change strategy, which had been accepted by the Government.
"There can be no picking and choosing from the strategy. It is a total package that can work only if all elements are in place," he said, adding it could be delivered on time at a projected cost of €8 billion.
But Mr Martin cautioned that the metro could be delayed by planning objections, reiterating the chamber's view that it should be fast-tracked as a nationally important infrastructural project.
While accepting that a full business case for the metro needs to be developed, he recalled that the DART was once pilloried as a waste of money, but now the debate was about how to extend it.
The Labour Party spokeswoman on transport, Ms Joan Burton TD, said it was apparent that Mr Brennan's policy on the metro was now "hopelessly mired in confusion and contradictory statements".
She called on the RPA to clarify its role in relation to the feasibility study carried out by KPMG and to publish immediately its conclusions and to explain how the figure of €20 billion was reached.
"This will undoubtedly be the most ambitious capital project ever in the history of the State and taxpayers are entitled to be fully aware of the direct costs and the full extent of interest and maintenance charges."
Branding the Minister's "hurried statement" yesterday as "nothing more than a desperate attempt to brush aside the reported conclusions of the consultancy study", she said its leaking was a matter of concern.
"We need to know what the status of this KPMG report is, what it reveals, what the Minister proposes in detail and how he proposes to finance the project", Ms Burton added.