An Bord Pleanála has refused permission for a major development of a junction of the Armagh Road/M1 motorway at Dundalk, Co Louth, after it found that it would be "contrary to the principles of good road design" and would "adversely affect" the carrying capacity of the national primary route.
It also ruled that the acquisition of lands for the scheme was "not necessary".
As a result, it said it would not be appropriate to approve the €5-€6 million scheme, which was due to be financed by local developers and had been submitted by Louth County Council for approval.
The planned development at the Armagh Road/M1 junction at Dundalk, would have led to the construction of two roundabouts, the realignment of the Armagh Road and of a link road from it to County Road, as well as the construction of a number of sliproads and auxiliary lanes.
But in a written ruling, the board said that partly due to the volume of locally generated traffic which it was predicted would be attracted to the motorway, it considered that the proposed development would also give rise to "weaving of high-speed traffic on the motorway".
This would result in "a reduction in the level of service for which the motorway was designed", and would adversely affect road users.
The board also ruled that the proposed development may have been seen "as a substitute for the provision of an adequate local road infrastructure to service proposed development in the general area".
This would tend to delay the "timely provision of the planned local road network," and would be contrary to the orderly development of zoned lands in Dundalk. Similarly, it said it did not accept its inspector's recommendation to approve the plan, as it considered that it would conflict with national policy.