Border checks will be an inevitable consequence of a no-deal Brexit, EU Commission President Jean-Claude Juncker has said.
In a blunt confirmation, he said Ireland would have to implement checks on the EU’s behalf – but insisted the UK would be entirely to blame.
With no sign of a breakthrough in the Brexit impasse, it means we could be just weeks away from seeing the return of trade barriers on this island.
“I’m not the architect of new Border stations. The British have to tell us exactly the architectural nature of this Border,” Mr Juncker said.
Taoiseach Leo Varadkar is to stress Ireland’s openness to “realistic” alternatives to the backstop when he meets British Prime Minister Boris Johnson in New York this week.
Meanwhile, it is understood that representatives of the British government, including ministers, have been privately briefing their EU counterparts and businesses in recent days that Ireland will cave on the backstop ahead of October 31.
Sources said the UK had tried to suggest the impact of a no-deal Brexit was being grasped in Ireland only now - despite repeated public warning from the Irish side about the economic and social impact it would have.
The Irish Government now believes the time to reach a deal is "shrinking rapidly".
Ongoing talks between Irish and EU officials over what form border checks will take are to intensify as the Brexit deadline approaches.
Mr Juncker said yesterday the backstop, which keeps the UK tied to many EU regulations, could be replaced if the UK found alternative ways of maintaining an open Border.
"We have to make sure that there will be no hard and physical Border between the two parts of the Irish island and things have to be done on a level playing field," he said.
However, he made it clear that for Ireland to remain in the EU's internal market, then it must be fully protected.
He said that in a no-deal Brexit, an animal entering Northern Ireland could then be transported into the EU via Ireland if there were no border controls.
"This will not happen. We have to preserve the health and the safety of our citizens," he said.
However, the EU chief argued that Brussels would not take any of the blame for what might flow from that scenario.
"I don't like a Border because after the Good Friday Agreement, and this Good Friday Agreement has to be respected in all its parts, the situation in Ireland has improved. We should not play with this."
Britain did submit tentative proposals for alternatives to the backstop last week, but they fell well short of what is required to preserve the EU single market without checks.
Foreign Secretary Dominic Raab yesterday dismissed suggestions that the UK could revert to a Northern Ireland-only backstop.
Pressed on whether Northern Ireland could have different EU customs arrangements than the rest of the UK, Mr Raab said: "No, of course, that would be wrong."
Mr Johnson has lined up a string of meeting with EU leaders on the fringes of a UN summit this week.
He is expected to hold talks with European Council President Donald Tusk, French President Emmanuel Macron and German Chancellor Angela Merkel.
A spokesperson for Mr Varadkar said he would use the opportunity to emphasise the need for "detailed, legally operable and realistic arrangements which achieve the objectives of the backstop".
Mr Varadkar also intends to argue that "engagements from the UK need to step up a gear in order to reach a deal".
The Taoiseach will have a separate meeting with Mr Tusk where he "will acknowledge the strong support of the European Council for the Withdrawal Agreement and the specific measures required to ensure no return of a hard Border".
Reacting to Mr Juncker's intervention, Fianna Fáil's Brexit spokesperson Lisa Chambers told the Irish Independent: "Without a Brexit deal, checks are virtually unavoidable."
She said it was time for the Government "to come clean with the Irish people about the conversations they have had with the EU Commission and what plan they have to protect the Good Friday Agreement and the single market in the event of a no-deal Brexit".
"We are less than six weeks away from the Brexit deadline, it's time for honesty and transparency from the Irish Government," she said.
British opposition Labour leader Jeremy Corbyn said yesterday his party would guide him on how to campaign in a second Brexit referendum, pledging to offer voters a choice between staying in the European Union and a "credible" deal.