The Brexit process started in March 2017 with the triggering of Article 50, allowing two years to complete the process. The main story since then has been of postponing difficult decisions in the hope that something would turn up. Ministers have insisted they have a mandate from the people but have struggled to agree on what it entails in practice. Negotiations within the UK government have been as difficult as those with the EU.

It might have been expected that, before March 2019, we would have a clear idea of what Brexit would look like. Instead, we have a 20-month “transition period”, which the UK government has been calling an “implementation” period. It is neither a transition nor an implementation phase, but the period in which the real negotiation of what Brexit means will take place; it can be extended once by agreement of both parties.

What has been achieved now is the minimum required for the formalities of withdrawal: the financial settlement; an agreement on citizens’ rights; and an ambiguous commitment on the Irish border question. The talk in recent months has suggested that the Irish border is the last remaining obstacle to a deal. This is misleading, as the Irish border stands in for a much larger set of issues on which discussions have barely begun – from the single market to trade to regulations.

Red, red lines …

At the beginning of the process, the UK government laid down a series of red lines. These included withdrawal from the single market, the customs union and the jurisdiction of the Court of Justice of the European Union, and no differentiated Brexit for the different parts of the United Kingdom. These have all been breached.

The Chequers agreement in July, which formed the basis of the UK negotiating position, conceded that the UK would align with EU standards in manufactured and agricultural goods, a central principle of the single market. The new agreement concedes the customs union in the form of a “single customs territory”.

This is purportedly to deal with the Irish border, but extending the customs union to the whole UK also serves a wider purpose. British manufacturers have been telling the government that they need a customs union to secure frictionless trade and their just-in-time production chains.

The Irish government wants to maintain access to markets in Great Britain. The idea is that the customs agreement is a backstop, to be superseded by an overall trade agreement with the EU. Yet, unless that agreement also includes customs union, it is difficult to see how it could serve the purpose – since you need customs union to prevent the hard border. The UK can also withdraw from it only with the agreement of the EU. And differential treatment for Northern Ireland is certain to spark demands for a special deal for Scotland, as the Scottish government proposed in December 2017.

During the transition, meanwhile, the UK will be subject to the Court of Justice of the European Union. Thereafter, disputes about agreements will be subject to binding arbitration, another form of supranational jurisdiction. Arbitration panels will have to follow the Court of Justice’s interpretation of EU law.

Like Oslo, but different

The UK will therefore remain tied to the EU and have to accept many of its policies. This bears comparison with the Norwegian model (the European Economic Area) that was explicitly rejected at the outset – though with some differences. The UK will be tied to the EU customs union, which Norway is not. It will not enjoy all the single market benefits, which Norway has (except in agriculture and fisheries).

It will not, like Norway, have a consultative voice in the making of EU policies. The UK will not be bound to accept free movement of workers, but this question might come back in return for access to EU markets, especially in services.

Finally, there is to be a differentiated Brexit for Northern Ireland, which will be more closely tied into the customs union and product regulation. There is to be a special designation of products as UK (NI), and a need to meet both UK and EU regulations.

Brexit was never going to be easy, especially after the UK government rejected off-the-shelf solutions such as the European Economic Area. What it has ended up with – customs union and bits of regulatory alignment – looks rather like the model at which the Labour Party, after its tortuous internal arguments has arrived, not that Labour will agree.

Had both parties started off with the Norway model, they might have found common ground and a clearer and more comprehensible arrangement. Instead, to cite Lewis Carroll, they have been hunting a Snark.

Michael Keating, Chair in Scottish Politics, University of Aberdeen.

This article first appeared on The Conversation.