Chief Executive of the Labour Relations Commission Kieran Mulvey has said it is too late for a blame game in the controversy surrounding the Garth Brooks concerts.
Dublin City Council has decided to allow only three of the five concerts at Croke Park to take place.
Garth Brooks has said that if he cannot play all five concerts he will play none at all.
Mr Mulvey, who acted as a mediator between residents and Croke Park to try to resolve the row over the number of concerts being held, said that Dublin City Council's decision cannot be amended or appealed.
Speaking on RTÉ radio, he suggested that the focus should now be on ensuring that a similar scenario did not re-occur.
Several hundred residents from the Croke Park area have called on the authorities to grant permission for all five concerts to go ahead at a rally held in Ballybough.
Speaking after the gathering Independent Councillor Nial Ring said "there is no doubt that a large number of locals want five concerts and I know that behind the scenes the Lord Mayor is doing his utmost to resolve the current situation."