The UK cannot use the Northern Irish border as a “test case” for its future customs relationship with the EU, Brexit chief negotiator Michel Barnier has warned.

However Barnier also said the imposition of a hard border between the Republic of Ireland and Northern Ireland needed to be avoided.

Speaking at a news conference following the publication of the EU’s, Guiding principles on the dialogue for Ireland/Northern Ireland, last week, Barnier raised concerns at the UK’s proposals for border arrangement with Ireland post-Brexit.

“What I see in the UK’s paper on Ireland and Northern Ireland worries me,” Barnier said, accusing the UK of wanting EU law, its customs union and the rules of the single market to be suspended at the border.

He added: “The UK wants to use Ireland as a kind of test case,” Barnier said, adding: “This will not happen.”

Barnier said it is important to preserve peace on the island and uphold the principles in the Good Friday Agreement.

But he insisted political decisions need to be made ahead of any technical decisions on how to cross what will be the UK's only land border with the EU after Brexit.


Traffic crossing the border between the Republic of Ireland and Northern Ireland in the village of Bridgend, Co Donegal.
Image PA Images

"We need to avoid a return to a hard border, while respecting Ireland's place in the single market. North-south cooperation will need to be preserved in all policy areas," he said.

Barnier said the EU recognized the “unique situation and the specific circumstances of the Republic of Ireland” and that he considered it a “special responsibility” to address Ireland’s concerns in his negotiations with Britain.

The Irish government reiterated its support for an open border post-Brexit last week.

“Our priorities remain protecting the Good Friday Agreement and the peace process, including by avoiding a hard border, and maintaining the Common Travel Area.”