London and Brussels are back to square one, as negotiations on future trade relations have reached an Irish dead end.

The European Commission published a 120-page draft withdrawal agreement on Wednesday, which envisages Northern Ireland remaining in the Customs’ Union, even if Great Britain leaves. The 168-articles describe a “common regulatory area” in Northern Ireland with freedom of movement for people, goods, and services.

While the European Commission’s chief Brexit negotiator, Michel Barnier, hailed this as a “key moment” in the negotiation, London saw the proposal as to the constitutional and economic integrity of the United Kingdom.

No sooner has the report been published, the British Secretary for Northern Ireland reiterated London’s commitment in the “constitutional and economic integrity” of the United Kingdom. Anticipating the publication of the report on Tuesday evening, No. 10 Downing Street issued a statement suggesting that the UK would not accept “anything that threatens the “constitutional integrity” of the UK. Later on Wednesday, Theresa May explicitly said in parliament that Brussels is threatening the constitutional integrity of the United Kingdom.

Karen Bradley said the British government remains committed to avoiding a hard border in Northern Ireland, but there would not be a separate trade agreement. That is also in line with the demands of the Democratic Unionist Party, whose parliamentary support is necessary for the survival of Theresa May’s governance. Since June 2017, the DUP not only has a domestic veto in UK politics but also in the future of Brexit negotiations.

The Republic of Ireland and the EU insist that the 120-page draft proposal merely reflects the common position reached between London and Brussels in December.

But the Republic and the EU do not regard the plan as interference in the UK’s domestic affairs of the UK. They see it as merely the honouring of an agreement already struck with Downing Street in December.

London agrees with the objective of avoiding a hard border in Northern Ireland but insists that objective is possible with the use of technology. For Brussels, unless there is regulatory alignment in principle across the island, there will be a hard border.

In this scheme, London and Brussels are back at square one, since no one in Brussels believes that a border can be avoided by “technical” means.