Dún Laoghaire-Rathdown County Council is expected to seek a court order lifting an injunction preventing work from proceeding on the controversial site of Carrickmines Castle on the M50.
The move is expected after an order given by the Minister for the Environment, Mr Martin Cullen, allowing for construction to resume comes into effect today.
Work on the site has been blocked since February by a Supreme Court interlocutory injunction, which was granted to protesters.
It was granted pending a full hearing into claims by the protesters that the authorities had not complied with relevant conservation legislation at the Carrickmines Castle site.
The road scheme involves removal of part of the earthwork defences, or fosse, belonging to the castle.
However, last month the Minister for Transport, Mr Brennan, said an order before the Houses of the Oireachtas would enable the council to have the injunction lifted.
The order by the Minister for the Environment, Mr Cullen, gives permission for the work to proceed at the site, which is designated as a national monument.