Five clues from the EU Withdrawal Act about the next phase of Brexit

Published on
6 min read

The way the Bill has been amended in Parliament on the way to becoming an Act offers some intriguing clues about how the next phase of the Brexit negotiations may unfold.

The way the Bill has been amended in Parliament on the way to becoming an Act offers some intriguing clues about how the next phase of the Brexit negotiations may unfold.


The basic purpose of the European Union (Withdrawal) Act is unchanged from when it was first introduced to the House of Commons: a way of avoiding a legal vacuum when the UK leaves the EU. The new legal framework it creates is explored in more detail in our earlier briefing here. There have been some significant modifications and refinements, but the core provisions remain largely intact.

The explanatory notes published with the Act explain its purpose as follows:
“The principal purpose of the Act is to provide a functioning statute book on the day the UK leaves the EU. As a general rule, the same rules and laws will apply on the day after exit as on the day before. It will then be for Parliament and, where appropriate, the devolved legislatures to make any future changes.”

The main aim of the Act is therefore to provide a workable fall back, while the Government works out how its relationship with the EU is going to develop. To what extent will it wish to retain at least some EU law in order to secure the right trading relationship with EU, and to what extent will it wish to go it alone?

Frustratingly for many, the Government has yet to put all its cards on the table. However this flagship Brexit Act does offer some important clues about how the next phase of the Brexit process is likely to progress.

Clue 1: A definite exit day

Much political capital has been expended on amending the Bill to change the definition of the exit day. The original Bill provided for it appointed by regulations made by the Minister. It is now defined as 11pm on 29 March 2019. This can be changed by ministerial regulation, but only if a different exit date is agreed with the EU.

This change may make little practical difference, but it serves to emphasise the Government’s aim to deliver at least a technical Brexit on 29 March next year.

Clue 2: Customs arrangements a priority

Another indication of the Government’s preferred timetable can be found in section 18, which was inserted during the final stages of the Bill’s passage through Parliament. This sets a deadline of 31 October 2018 for a ministerial statement about the steps the Government intends to take to secure a “customs arrangement” between the UK and the EU.

The EU has repeatedly said that negotiations on the withdrawal agreement and the outline of the future relationship must be completed by that date, so this is at least an acknowledgment of that reality. It can also be seen as a victory of sorts for those in the Government favouring a softer Brexit. It will be interesting to see how this provision interacts with the Trade Bill, which is due to reach its report stage in the House of Commons later this month.

Clue 3: A meaningful vote is going to be difficult

Given the constraints of the timetable, with the clock ticking inexorably towards 29 March, how can MPs be given a “meaningful” vote on the deal? That issue proved to be one of the main points of contention between the Lords and the Commons, and indeed between the Government and the “Tory rebels”.

Section 13 of the Act is an elaborate attempt to square the circle. In much simplified form, it says that the withdrawal agreement may not be ratified unless both the withdrawal agreement and the framework for a future agreement have been laid before Parliament and approved by a resolution in the Commons and a motion in the House of Lords. An Act of Parliament implementing the withdrawal agreement will also be required.

But what happens if the withdrawal agreement is not ratified in this way? The Act includes provisions for a statement to be made by a Minister of the Crown about how the Government intends to proceed, which will then be the subject of further motions in both Houses of Parliament. It also provides for a ministerial statement to be made to Parliament if no agreement has been reached by 21 January 2019 – another clue as to how the Government views the Brexit timetable.

Clue 4: The way is open for reversing the effect of the Act, at least in part

Section 19 is another provision which was not found in the original Bill. It provides that nothing in the Act is to prevent the UK from “replicating in domestic law” any EU law made after exit day, or from continuing to participate in EU agencies (which are likely to require such a step in their areas of competence).

The doctrine of the supremacy of Parliament means that an Act of Parliament is always subject to amendment or repeal by a later Act. But it is rare for this to be expressly acknowledged in this way in the main body of an Act. That means that the Government is prepared to live with the principle that the EU Withdrawal Act, despite its major constitutional significance, is likely to need modification in the near future.

Clue 5: Devolution issues are fiendishly complicated

We have become used to grappling with the complexities of the EU single market, but with the exception of the North/South border in Ireland, much less attention has been given to the UK’s internal market, or the impact of Brexit on the devolution settlement which was formulated on assumption that the UK would remain part of the EU.

The impact of Brexit on devolution legislation was addressed in a short clause in the original Bill. Now section 12 in the Act, it has expanded considerably, and now incorporates an even longer schedule of detailed amendments. Again, the Act has opted for an interim resolution which is described in the explanatory notes as follows:

“The Act amends each of the devolution statutes (the Scotland Act 1998, the Northern Ireland Act 1998, and the Government of Wales Act 2006) so as to remove the requirements that the devolved legislatures and the devolved administrations can only legislate or otherwise act in ways that are compatible with EU law. It then inserts powers into each of those Acts to apply, by regulations, a temporary ‘freeze’ on devolved legislative or executive competence in specified areas, so that in those areas the current parameters of devolved competence are maintained.”


There is much more detailed legislation to come to implement Brexit, not least the 800 or so statutory instruments which the Government estimates will be required to make legislation retained from the EU work in a purely domestic context.

Now the Withdrawal Act has become law, this detailed work can begin and Government seems to be committed to completing this process by 29 March 2019. However it remains more than a remote possibility that the terms of the withdrawal agreement will mean that the UK will remain in full alignment with the EU well beyond that date. That would mean either major amendments to the brand new Withdrawal Act, or significant changes to the current Brexit timetable.


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