120 social and affordable homes planned for a site in Cabra in Dublin will have to make way for Luas tram parking.
It's expected only 50 to 60 units will now be built because a third of the site is being requisitioned as part of the extension of the Luas to Finglas.
The Irish Times reports transport bosses were unaware the Bannow Road plot had been bought by the city council when it was selected as a stable yard for trams.
They have told councillors there is no alternative space for parking trams on land within the M50.
Work on the homes was due to begin at the end of the year.