The Department of Defence is to appeal the decision to grant planning permission to the Football Association of Ireland for Eircom Park at Saggart in south-west Dublin.
A spokesman for the Department confirmed last night it remained "implacably opposed" to the proposed 45,000-seat stadium and would immediately appeal to An Bord Pleanala, which could delay or prevent the proposed development.
The FAI president, Mr Pat Quigley, nonetheless expressed delight at the decision to award planning permission, with 23 councillors voting in favour and none against.
Permission was subject to 40 conditions, but in effect the council rejected the Department's submission that it could compromise safety at the nearby Casement Aerodrome at Baldonnel, although the local authority has sought an independent aviation safety report on the possible impact of the stadium..
The decision came hours after the Taoiseach held a press briefing to outline the Government's plans for the National Stadium at Abbottstown in north Co Dublin, which is to and cost more than £300 million.
Mr Ahern confirmed it would include an aquatic and leisure centre, including a 50-metre pool to be built in time for the Special Olympics in 2003.
He said he had made it clear to the FAI that if it joined the Abbottstown venture it could benefit from £40 million in funding from the sale of corporate boxes.
Mr Ahern had been accused by the Labour TD and councillor, Mr Pat Rabbitte, of trying to influence Fianna Fail members on the authority. But two Fianna Fail councillors were absent due to long-standing engagements and six others voted in favour.
