Leo Varadkar's been criticised for opposing a high-rise building in his own constituency.
It comes as the Taoiseach encouraged councilliors to look favourably on such developments in their own areas to increase housing supply.
Writing in the Sunday Independent, he suggested high-rise quality apartments should be built at Poolbeg.
But in a letter to Fingal County Council dated February 2017, Mr Varadkar voiced opposition to plans for four-storey apartments in Castleknock.
In his letter he writes: "To begin, four storey apartment blocks are a design model which has long fallen into disfavour.
"Yet these type of apartments are a key feature of the Absainte Ltd scheme.
"It would be grossly insensitive of local feelings to permit such dated architecture to succeed."
Image: Fingal County Council
Fianna Fáil leader Micheál Martin says houses will never be built if that's the attitude.
"So on the one hand they were told, in an article in the Sunday Independent, that high-rise is the way to go... meanwhile he's objecting to a high-rise development in his own constituency.
"And he's doing it on the grounds that it will reduce the value of housing around in the neighbourhood.
"Now we do want to make housing affordable for people - and if our only interest is to keep the value of housing up, we're not going to build any new houses at all".
