There is to be a full High Court trial of the constitutional issues involved in the construction of the final section of the M50 at Carrickmines. The case is due to begin next Thursday.
Both sides have agreed that work concerning archaeological remains at the site will be halted until 11am on Thursday morning. Work on other areas will continue in the meantime.
The final section of the motorway had been delayed for almost two years, due to legal challenges concerning the remains of a medieval castle which lie in the path of the M50.
An earlier High Court ruling found the Minister for the Environment had no primary legislation to allow him to make an order for the destruction of what remains of the castle.
However, last month new legislation was passed to allow work to continue.
Diggers returned to the site on Monday, but campaigners claim the move is unconstitutional.
Mr Justice Michael Peart yesterday ordered lawyers for Dún Laoghaire-Rathdown Co Council to produce detailed
affidavits setting out the work being carried out on the ruins of the castle.