Government no deal Brexit emergency plans for Rosslare Europort which are seen as crucial to ensuring Ireland's continued access to continental Europe may not be ready for up to five years.
Labour leader Brendan Howlin made the claim as he urged the Government to reveal the exact details and timelines of its Brexit contingency plans instead of simply re-stating top-line initiatives to the public.
Speaking to reporters at Leinster House as British MPs prepared to vote on the UK-EU Brexit deal, Mr Howlin said the reality is time is running out to avoid a no deal crisis.
While welcoming the Government's decision to begin drawing up legislation to protect Ireland, he said serious concerns remain over how long the protections will take to implement.
And noting concerns over Rosslare Europort in his own Wexford constituency, Mr Howlin said there are fears some of the Brexit defences will not be in place for as long as five years.
"There's great plans for a new customs facility there and I understand the indicative drawings are going to be prepared, but the port authorities tell me they should have it in place between three and five years from now.
"Now, obviously there's going to be an emergency happening at the end of March, and it really will be all hands on deck. But we really need to have indicative planning.
"I talk to customs officials down there, and they don't know how many officials are they getting. They pointed out the bar area in Rosslare port is apparently going to be taken over by the Office of Public Works, but right now, 73 days to Brexit, it's still a bar.
"That concerns me greatly," he said.