Minister for Employment Affairs and Social Protection Regina Doherty has said that she has "absolutely no confidence" that the North-South Interconnector project will ever be delivered.
The comments come after two reports were brought before the Dáil this week, recommending that the controversial project should proceed overhead on pylons despite local opposition.
Speaking on LMFM today, Ms Doherty, TD for Meath East, said that "there are more obstacles to this project that there were at any other stage in the last 14 or 15 years".
The North-South Interconnector is a €286m investment that will connect the electricity grids of Ireland and Northern Ireland. The 400 kilovolt line will run through counties Monaghan, Cavan and Meath in Ireland, and Armagh and Tyrone in Northern Ireland.
EirGrid has said the interconnector will underpin the efficient operation of the all-island electricity market, fixing a bottle-neck that cost millions of euro every year and applying downward pressure on electricity prices.
Ms Doherty, who is against the overhead pylons for the project, said that there are several legal obstacles to the project, as well as the issue of Brexit.
"The first obstacle is local to the Republic, where a Supreme Court hearing is set for two days next week on a judicial review of the project to date.
"The second legal obstacle in the way is an appeal on behalf of the institutions of Northern Ireland to their Supreme Court, with regard to the decision taken by a court up there to overrule the decision making process for the granting of the overhead lines in Northern Ireland."
"But we probably have the biggest obstacle of all facing both north and south in the coming weeks and months, which is Brexit."
The reports published this week found that the cost of both the overhead line and underground cable solutions has increased. However the underground solution is more expensive by around €450m, according to the latest report.
But Ms Doherty said today: "I think there is huge solidarity among the entire Republic of Ireland against overgrounding of cables. I doubt you would find anybody who would be in agreement to a huge pylon in their back yard, or having a very high voltage cable passing through where their children play."
The minister added that she thinks Minister for Communications Denis Naughten "has no choice but to express confidence" in this process.
Ms Doherty said that she has not had a one-to-one chat with Mr Naughten since the reports were released but said that she "has respect" for him and "understands that he has to do a job".
"I don't have any more confidence in the delivery of this project than I would have had in the last number of years," she said.