Tanaiste Simon Coveney has said there will be a considerable degree of scepticism in Brussels to the UK’s protocol on Northern Ireland, particularly in relation to customs controls.
Mr Coveney said while the UK has left the EU, Northern Ireland will remain in the EU’s custom zone and British officials will have to adhere to European controls in the province.
He said the document does not alter the legally binding Withdrawal Agreement between the UK and the EU which he said guarantees that there will be no physical customs infrastructure on the island of Ireland.
While he gave the document a cautious welcome, Mr Coveney said extensive technical discussions between the UK and the EU negotiating teams will be needed to clarify the arrangements.
Mr Coveney, speaking on RTÉ news, described the protocol document as an implementation plan proposal from the British Government but that cannot alter or undermine what was signed up to in the Withdrawal Agreement.
Meanwhile, the possibility of customs checks on the Irish border grew more likely today following the publication of implementation guidelines for the Irish protocol today by the British Government, said Fianna Fáil MEPs Barry Andrews and Billy Kelleher.
“We are alarmed at how the British government is interpreting the Irish protocol. Some of the language used in the implementation guidelines is worrying. What the British government is proposing is quite light touch. We believe it could cause the European Commission to question whether keeping the trade border in the Irish Sea is still viable,” they said.
The pair said their worry is that in this scenario, the Commission would be forced to insist on customs checks on the island of Ireland in order to protect the European Internal and Single Market. “This is something we, and the majority of people on the island of Ireland, would oppose,” they said in a statement.
The north's First Minister and DUP leader Arlene Foster welcomed "clarity" with the publication of the UK paper on Northern Ireland and Brexit.
"I think there's been some clarity brought today. Of course we'll continue to work on the technical parts and the entry designation for SPS and animal origin matter will, of course, have to be dealt with," she told Stormont's Executive committee.
"I think the important point in the protocol from what I can see thus far is it talks about very much minimising all of that. I welcome that," she said.
Obviously I didn't like the protocol at all but we have to make sure we minimise it as much as possible.