What would it take for the UK to rejoin the EU? Anthony Salamone sets out how the UK would have to change and the demands the Union would make. Abandoning its opt-outs, the UK would have to start from scratch and accept being a more normal member state – and thus make its second EU membership much more positive and inclusive.

With Brexit now imminent, proponents of EU membership are already considering the possibility of the UK rejoining the EU in perhaps five or ten years’ time. This prospect raises important political questions which would have to be addressed before the UK took even the first step towards renewed membership.

Article 50 TEU is famous for its brevity and has been subject to interpretation throughout the process of Brexit – most definitively by the EU Court of Justice, in its ruling that a member state’s withdrawal notification can be unilaterally revoked. However, on rejoining it is perfectly clear. A former member state seeking to return must apply under Article 49 – that is, the normal accession procedure.

The UK would have to start from scratch: a letter of application to the European Council, assessment of its candidacy by the European Commission and a decision by the Council on whether to make the UK a candidate country. If successful, the subsequent processes of negotiation, ratification and implementation would have to follow. While these steps would have a flair of the bizarre, given that the UK was previously a member state for 47 years and a powerful member at that, the EU is a legalistic organisation bound by its treaties. It would be unwise for the UK to push for a different accession procedure. Instead, it could accelerate the process by ensuring that its laws and policies meet EU standards and by fulfilling all the requirements placed upon it expeditiously.

The UK would have to demonstrate that it satisfied the Copenhagen criteria for EU membership, and secure agreement from the member states that they had the political will and the EU had institutional capacity to readmit it. Enlargement requires unanimity – so would any member potentially veto the UK’s application?

In present circumstances, we might imagine countries like Germany (big country ally), Ireland (most adversely affected by Brexit), the Netherlands and Denmark (like-minded partners) and Poland (many citizens living in the UK) being particularly supportive. France could likely protest in some form, but might be persuaded in the end if it was content with the UK’s accession terms.

These political dynamics would depend in large part upon how the UK conducts itself in the Brexit era. The UK’s approach to the forthcoming future relationship negotiations, how it treats EU citizens and their families, and its trade, tax, social, environmental and labour regimes in the years ahead would all be factors. The shape of the EU-UK strategic partnership would also be an important consideration.

A successful future application for EU membership would have to be predicated upon a new political consensus in the UK. The EU would look for significant, stable and long-lasting majority public opinion in favour of rejoining. Support for EU membership on the order of 60-65 per cent or more for several years would likely be a minimum standard. If the UK were to bid for membership in the absence of such consensus, its application would undoubtedly be rejected. The EU will not voluntarily import an unstable member state or risk another Brexit down the road.

The EU would also expect any application to be on the understanding that the UK would be a more normal member state. The UK’s major concessions during its first EU membership – the budget rebate, opt-outs on the euro and Schengen, special justice and home affairs arrangements – would not be on offer. The UK was largely responsible for the opt-out culture, which is still bemoaned by much of the Brussels establishment. The European Commission is currently seeking to eliminate all budget rebates (following from the UK, other countries have rebates and ‘rebates on rebates’) for the next Multiannual Financial Framework.

As a full participating EU member state, the UK would resolve outstanding issues. Its regular membership would allow Ireland to join Schengen and put pressure on Denmark to give up its euro opt-out.

The question also arises of whether the EU might adopt a formal multi-tiered membership structure – and the UK could instead join an outer tier. However, the EU will be unlikely to move in that direction in the foreseeable future, not least due to opposition from those member states which fear being relegated to the outer tiers.

During the accession process, the UK would have to undo whatever divergence it had effected from EU values and standards in the Brexit era and converge back with the EU acquis. Depending on its depth, the EU-UK partnership could be the basis for the pre-accession phase, potentially complemented by a new Association Agreement. If the UK did in future depart from the European Convention on Human Rights – either by leaving the Convention or suspending implementing Court judgements – the EU would insist it fully reintegrate into that as well.

Provided it was successful in rejoining the EU, the UK would have the opportunity to conduct its second EU membership completely differently. It could develop a comprehensive EU strategy, outlining its major policy themes and priorities for the EU and setting out the UK’s positive and forward-looking vision for Europe. The UK could put in place structures to include the devolved political institutions of Scotland, Wales and Northern Ireland (assuming they all remain in the UK) in its EU decision-making, providing them with genuine access and influence.

Renewed EU membership would require the UK to become fully integrated into the core of Europe. Its pursuit would have to be grounded in major UK-level political change and a new consensus on the EU. Once the UK experiences the Brexit era, with diminished influence and voice in the world, perhaps opinion in England and Wales will shift and people will look to regain some of what has been lost. Seeking to rejoin the EU would have to result from genuine reflection, not expedient self-interest. After the Brexit saga, the UK will owe that much to the EU – and to itself.

This post represents the views of the author and not those of the Brexit blog, nor LSE.