This is a short high-level, technical guide on how UK/EU relations could be improved up to and including re-application for full membership.
It’s worth noting that the first steps on this path would also be taken by any political leader seeking to “make Brexit work”. In practice, a single UK PM would be unlikely to complete the process since this would take at least two or three Parliamentary terms in normal times (see scenario below). I would expect it to be a wholly new generation of politicians who would complete the process, presumably supported by a new generation of voters, committed to EU membership.
The pathway back – building a future UK/EU relationship
Phase 1: Normalisation
The damage of the last few years has to be repaired and trust restored before we can take any steps to an enhanced relationship with the EU.
The first requirement is the resolution of issues around the Northern Ireland (NI) Protocol, currently the major irritant in the relationship.
There must be agreement on the status of and possible repeal of the current NI Bill or the passage of new legislation to neutralise it.
There must be agreement on the outstanding issues relating to the NIP. Achieving this includes ensuring that the DUP do not obstruct the functioning of the devolved administration in Stormont.
There must be a full operational implementation of the amended agreement on both sides.
The policy of successive Conservative governments since 2016 has been to use the situation in NI as a “lever” in a manner that is equivalent to blackmail.
Without the positive steps on the NI issue, any improvement in relations with the EU will always be seen as “hostage” to renewed threats of blackmail.
Phase 2: Enhancement
Work towards a successful review of the EU–UK Trade and Cooperation Agreement (TCA) in 2025/6.

Reconsideration of the EU programmes in which the UK could participate, for example, Erasmus and Horizon.
Consideration of measures that would further ease UK/EU trade:
- An SPS agreement (sanitary and phytosanitary measures agreement to allow mutual recognition of methods of control and inspection to verify food standards compliance, which would immediately improve and resolve further North/South Irish issues),
- An agreement to stay aligned with most EU regulations, which implies internal UK clarity on what role regulation plays in industrial and trade policy,
- Maintenance of a level playing field, competition law, and so forth, for a defined period to minimise further divergence, and facilitate a return to the Single Market, if this is deemed desirable further down the road.
A mutual agreement on the judicial arrangements governing the operation of agreements; this implies clarity about, and acceptance of some role for the European Court of Justice (ECJ).
The creation of new programmes for UK/EU cooperation and the restoration of more structured cooperation in other areas, e.g. policing, immigration, foreign and security policy.
Consideration of UK participation in the Single Market via: re-entry into the Customs Union or creation of a new UK/EU Customs agreement.
Once this is agreed, consideration can be given to participation in the Single Market, whether directly as a full member or, through a transition arrangement which might give the UK some say in new regulations, in advance of full membership. Direct participation as a full member of the Single Market includes acceptance of the four freedoms – goods, capital, services and people.
Phase 3: Enhancement
Creation of a new UK/EU Association Agreement, leading to participation in a broader range of EU programmes.
Phase 4
Opening of discussions on the UK’s re-application for EU membership under the terms of Article 49 of the EU treaty.
What do we need to do to follow this path?
The UK needs to be able to show that:
- There is a consistent majority in the UK in favour of improving relations with the EU. To be demonstrated by the election of a government or successive governments, which include improving relations with the EU in their manifesto commitments.
- The political system in the UK provides the long-term stability needed to ensure strategic commitment, which means that the election of a new government will not immediately undermine the long-term aim of improved relations with the EU.

Conclusion
The path sketched out has no timeframe, and the process could be paused, stopped, or accelerated at any point.
The EU is facing a difficult period, with considerable turbulence among the member states and other international challenges. The Member States might see the improvement of relations with a neighbour which is a reasonably influential political and security partner, with a large market, as a benefit that might smooth some of the turbulence. Nonetheless, there is unlikely to be any appetite for reintroducing a troublesome member state.
An underpinning of good bilateral relations with the EU Member States will be vital to any successful redefinition of the UK’s European Union relationship.
Simon Pease is a former UK diplomat.