The Kildare county engineer has expressed frustration that work on the Kildare bypass has been held up by environmental concerns.
Speaking on RTE radio, Mr Jimmy Lynch said that while £6 million worth of "preliminary projects" had been carried out, the main contract was "temporarily suspended pending the resolution of an environmental difficulty".
The council has spent £3 million on a new bridge over the Dublin-Cork railway line in preparation for the bypass.
About another £3 million has been spent on a surface water outlet pipeline and accommodation works for the National Stud. It is estimated that the main project will cost £50 million. An Taisce says the road would drain water supplies from the Pollardstown Fen area.
However, Mr Lynch said the council had carried out an environmental impact study, which recognised the impact on the fen as "a potential difficulty", but concluded that the impact would be insignificant.