Lord Trimble is a former First Minister of Northern Ireland and Leader of the Ulster Unionist Party. He won the Nobel Peace Prize for his role in securing the Belfast Agreement.

Michel Barnier has written that the backstop “is not about changing the constitutional status of Northern Ireland. That is none of the EU’s business…” Yet that is precisely what the backstop does do. He goes on to claim that “the backstop fully respects the carefully negotiated balance found in that Belfast/Good Friday Agreement between competing political views and different identities in Northern Ireland”: he is wrong – he is riding rough shod over our Agreement. That is why Unionists oppose it and why the Government, having listened and learned, now insists that the backstop must go.

It is true that the current backstop avoids a hard border on the island of Ireland, but it does so at the expense of the ‘”carefully negotiated balance” found in the Agreement.

The European Commission recently confirmed its view that ‘the backstop provided for by the Withdrawal Agreement is the only solution identified that safeguards the Good Friday Agreement, ensures compliance with international law obligations and preserves the integrity of the internal market’. They are wrong.

The backstop is not a legally operational solution, as it is not in keeping with the spirit and letter of the Agreement. I set out the detailed arguments as to why this is the case in an article for Policy Exchange in July this year. In summary, the backstop undermines the core principles of the Agreement – consent and agreement between equals that runs across all three of its strands – and it changes the status of Northern Ireland contrary to the Agreement.

In doing so, it risks the constitutional stability that Northern Ireland has enjoyed for over 20 years and undermines the principles that determine how it is governed. Devolved powers are reduced and a democratic deficit created.

In imposing a new basis for North-South co-operation, the backstop overrides the consent model established by the Belfast Agreement and sets out not to protect the economic co-operation that exists but to actively create an all-island economy that does not currently exist. The Belfast Agreement accords specific provision for the North-South Ministerial Council matters to be heard on matters relating to the European dimension, “including policies under consideration in the EU framework. Arrangements are to be made to ensure the views of the Council are taken into account and represented appropriately at relevant EU meetings”: they are not under the backstop – a clear breach of the Agreement.

The means by which the architecture of the settlement created by the Agreement has been re-negotiated are far removed from those that led up to the agreement made in Belfast in 1998; this was agreed through negotiations between the Northern Ireland parties and between the UK and Irish governments, so that there was ownership of what was agreed both in Northern Ireland and between the governments. How different the Withdrawal Agreement negotiations have been.

The Government now accepts the main points of my argument, and an August letter from the Prime Minister to Donald Tusk states that ‘..it has become increasingly clear that the backstop risks weakening the delicate balance embodied in the Belfast (Good Friday) Agreement…’

The Commission certainly has expertise in what is required to ensure the integrity of the internal market, but it does not have the expertise to make a judgment on what does or does not uphold the Belfast Agreement. It does not have, nor should it claim to have, the authority to decide upon this.

Here lies the problem right at the heart of the failure of the Brexit talks. The Commission alone, on behalf of the EU27, is negotiating the terms of the UK’s withdrawal; yet the subject matter on which we are all stuck is an area that is not entirely within the jurisdiction of the EU. The EU recognises in its original negotiating guidelines of 2017 the bilateral arrangements between the UK and the Republic of Ireland; these include the Agreement – an international treaty between two sovereign states which allows no third party arbitration and no alteration without the approval of both governments and, where necessary, that of the parties in Northern Ireland too.

Despite the wide-ranging remit accorded to the Commission to negotiate the terms of UK withdrawal, those powers do not include negotiating changes to areas covered by the Agreement. Under its terms, where difficulties arise they must be addressed by the parties to the Agreement – that is, either amongst the parties in Northern Ireland or by the two governments. There can be no derogation of sovereignty and no application of force. So sensitive is this matter that when the Republic agreed to accept the compulsory jurisdiction of the International Court of Justice in The Hague, in 2011, it did so for all matters other than those concerning Northern Ireland.

Given that the EU has no jurisdiction over matters governed by the Agreement, it is acting ultra vires. This means that it is exceeding its authority, and I dare say capability, in determining how the Republic of Ireland can ensure the integrity of the Single Market and, along with the UK, avoid a hard border whilst upholding the Agreement.

The EU may insist that the Single Market’s integrity is upheld on the border, as it does for all third country borders, but on the island of Ireland it is entering a mix of responsibilities and obligations, some overlapping, between itself and between those of the UK, Ireland and the Northern Ireland Assembly. This imposes limits to the reach of the EU’s authority in the current negotiations, and imposes responsibilities and obligations on the UK and the Republic, as well as the devolved institutions.

Until this is acknowledged, we are unlikely to find a way though to a solution. The point has come at which bilateral talks between the UK and Ireland and Belfast and Dublin are needed to break the impasse. Responsibility and sovereignty lies with the governments to work out a means of balancing the requirements of the Agreement and the Single Market’s integrity, with the aim of avoiding a hard border. The EU is committed to supporting the Belfast Agreement and the peace process; it surely cannot be beyond it to allow for flexibility in the application of some of the common commercial rules, as allowed for in the TFEU (Treaty on the Functioning of the European Union).

By handing back the problem of the border to the UK, the Republic and the relevant parties, the EU would be giving the responsibility for the solution where it ought to lie and to the only two states that together can solve the challenge it presents. As I said in my Policy Exchange article, much is said of what technology and systems can do to prevent a hard border, but little about the necessity of consent, agreement and co-operation.

The Prime Minister is fond of saying that “where there’s a will, there’s a way”. Whilst the EU continues to present the backstop as a legally operational solution, which it is not, it has no incentive to replace the backstop; while Dublin is allowed to avoid its bilateral obligations ,it has no incentive to co-operate.

It is time that the UK set out in full its concerns about the backstop, the limits of multilateral negotiations and the requirement, as well as the necessity, for bilateral negotiations with the Republic to find solutions for the border on the island of Ireland.

There will have to be compromises on all sides, new areas of co-operation and real partnership if these challenges are to be overcome. It can be done: it was in 1998, and I will not forget the efforts made by Bertie Ahern to understand our concerns and accommodate them in the last few days.

However, such compromises will neither be reached by pretending that the Protocol is fit for purpose, nor by putting the onus on the UK to come up with solutions on its own — neither are required under Article 50 nor under the terms of the Agreement: on the contrary.

The foundation of the Agreement is good relations between the UK and the Republic ,and the operation of consent and agreement between the parties in Northern Ireland. We now have an opportunity to revitalise our relations and co-operation in order to solve the outstanding areas of disagreement in the Withdrawal Agreement; not only that, but to do it in such a way that British-Irish relations are strengthened and the architecture of the Belfast Agreement utilised and extended, not simply “protected”. That would be a big win for all the peoples of these islands and for the principles that govern our relations.