Taoiseach Leo Varadkar has called for an alternative option to be found for the Metro North project to avoid it running under the grounds of a GAA club on the north side of the city.
It has been proposed that the service would run directly under Na Fianna's grounds in Glasnevin, which is in the constituency of Minister for Finance Paschal Donohoe.
The club will be required to relocate for at least six years if the proposed route gets the goes ahead.
The National Transport Authority expects the project to be operational by 2027 once it passes through the planning process.
However, the Taoiseach told the Dáil today that he shared the concerns of colleagues about the proposed route, including those of Mr Donohoe.
He said his message to the National Transport Authority and Transport Infrastructure Ireland was that they should look for an alternative option.
'Find an alternative option' – Taoiseach's message to planners of Metro North pic.twitter.com/bZitUlLktM— RTÉ News (@rtenews) May 1, 2018
"I am very concerned and I share the concerns of leaders, and other deputies, not least the Minister for Finance about this emerging preferred route," he said.
"I think it would do enormous damage to that club Na Fianna and to Home Farm as well and to Scoil Caitriona.
"There is a planning process that involves a railway order but certainly my message to the National Transport Authority and TII would be to find an alternative, to find an alternative option to digging up this really important club, which is the heart and soul of this community in that part of Dublin."
Mr Varadkar was responding to Fianna Fáil leader Micheál Martin. who said there were 3,000 members of Na Fianna and "this is their home, its the hub of the entire community".
"And so the value of voluntary human endeavour which civilises society is without a moment's thought, wiped out by a proposal such as MetroLink."
A spokesperson for the National Transport Authority said this evening that the consultation process around the MetroLink preferred route will continue until 11 May.
"We are happy to consider all submissions and proposals that we receive and we have made a commitment to report back as soon as practicable after that date," he said.
Chairman of Transport Infrastructure Ireland Michael Nolan said this evening that the public consultation gives an opportunity for improvements and avoidance of impact while preserving the benefits and objectives of the scheme.