An Taisce has questioned a decision by An Bord Pleanála to hold an oral hearing into just 25 out of 120 applications for billboard sites throughout Dublin.
Under a deal between Dublin City Council and international advertising agency JC Decaux, the city is to be provided with free bicycles in return for permission to erect the billboards at key city locations.
Two types of billboards are proposed, 70 boards which are free standing and cover an area of up to seven square metres, and 50 smaller boards which are about the size of a bus-shelter poster.
The larger billboards may carry moving images and be illuminated at night. The advertising space value to Dublin City Council has been estimated at more then €8 million.
Some 500 bicycles are to be provided by JC Decaux for Dubliners to use and return, in a deal similar to that done with other European cities.
However, concern has been expressed that Dublin is getting a worse deal than other cities.
In Paris, for example, the company is to provide 20,600 bicycles in return for 1,628 billboards, a ratio of almost 13 bicycles to each billboard, three times the ration being offered to Dublin.
While the Dublin contract also envisages the provision of some street conveniences, the Paris one envisages an annual rent of more than €2,000 a unit for 10 years.
A spokesman for An Taisce claimed that in Lyon, France, a city with a population similar to Dublin, 3,000 bicycles had been made available - six times more than here.
However, Dublin City Council has refused to release the exact nature of the deal, citing "commercial sensitivity".
Following the announcement by An Bord Pleanála that it intended to hold oral hearings into applications for just 25 sites, an spokesman for An Taisce called for each site to be afforded the same level of scrutiny.
"Some of these are in narrow city streets where their size alone may constitute a safety hazard, with posters blocking drivers' views of traffic lights and sign posts. In other areas, there may be streets of architectural amenity which these things will destroy. It is unbelievable that the city could even consider this."