Transport Minister Paschal Donohoe is calling on both sides in the Luas dispute to re engage with the Labour Court.
The company that operates the Luas says it could lose up to €100,000 per day if a strike by drivers goes ahead tomorrow.
Transdev says it cannot afford pay increases of up to 54%, which staff have asked for.
But workers says it has been five years since they've had a pay rise and they'll down tools in two 48-hour work stoppages starting tomorrow.

Transport Minister Paschal Donohoe says thousands of commuters who rely on the Luas will be massively inconvenienced.
Managing Director of Transdev, Gerry Madden, says industrial action will make their finances worse: But Eoin Reidy, from trade union SIPTU which represents drivers, says increased Luas profits mean Transdev can easily afford pay rises: