Concern has been raised about the pressure 300 new homes in South County Dublin would put on public transport services there.
Permission has been granted for the development beside the British Ambassador's residence in Leopardstown.
Local Sinn Féin Councillor Chris Curran says it would double the local population of an already congested area:
Mr Curran said: "With the Metro upgrade taking place, it looks as if we're going to lose the Luas services in that area for about two years.
"So, the traffic aspect of it is going to get far, far worse over the next two to three years. But in the main, I certainly welcome the development."