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UK–EU future relationship: UK ratification

On 24 December, the UK and EU reached an agreement to govern their future trading and security relationship from the end of the Brexit transition peri

On 24 December, the UK and EU reached an agreement to govern their future trading and security relationship from the end of the Brexit transition period.

But the UK government must ratify and implement the treaty to give it any effect in UK law. On 29 December the government published the European Union (Future Relationship) Bill to implement the treaty. It is expected to be fast-tracked through Parliament, completing all stages on 30 December.

The EU will also need to ratify any deal: find out more about that process.


What does the UK need to do to ratify a deal?

Under the Constitutional Reform and Governance Act 2010 (CRAG), the UK government can ratify a treaty once it has been laid before parliament for 21 sitting days and the Commons hasn’t voted to delay ratification. The government can avoid this requirement either by:

  • passing an act of parliament that provides that CRAG is not to apply to this treaty (as it did for the Withdrawal Agreement), and as proposed in the EU (Future Relationship) Bill, or
  • under CRAG, a minister can declare that “exceptionally” the treaty should be ratified without the 21 sitting days requirement being met.

In theory, this gives the government the power to ratify the treaty. But the UK has a longstanding principle that it does not ratify treaties until all the legislation needed to implement them is also in place – and the government has also acknowledged it will need to legislate.[1]

How can the UK ratify a deal?

There are four ways that the government can implement a deal.

  1. Use secondary powers under existing legislation.
  2. Pass an enabling bill.
  3. Pass a bill to implement the agreement clause by clause.
  4. Pass a bill to give the agreement direct effect

The European Union (Future Relationship) Bill uses a mix of these methods. 

  • Clauses 31, 32 and 33 provide broad Henry VIII powers enabling the UK government and devolved administrations to amend domestic law (including acts of parliament and the future relationship act itself) to give effect to the deal reached with the EU. Additional powers covering specific topics are included throughout the bill (option 2).
  • Various clauses of the bill implement aspects of the deal directly, including provisions on law and justice cooperation and international road haulage (option 3).
  • Clause 29 states that existing domestic law is to be treated as subject to the UK-EU deal even when it has not been specifically amended to implement it (and such amendment is required to give effect to the deal). This is a legally unusual provision and appears to be a form of direct effect (option 4).

Option 1: use secondary powers under existing legislation

What does this involve?

There will be areas where the UK has already put the necessary legislation in place to give effect to the deal: for example, where it has copied over EU regimes, such as in the case of protected food names, under the EU Withdrawal Act. In other cases, the government may have powers under existing acts of parliament to pass the regulations (secondary legislation) necessary to implement the deal. For example, any tariff reductions the UK and the EU agree can be implemented using a negative procedure statutory instrument (SI) made under Section 9 of the Taxation (Cross-border Trade) Act 2018.

Why might the government choose to do this?

This would avoid the need to pass primary legislation that can be amended and would be subject to votes in both Houses of Parliament. Some of the SIs the government would have to pass would be subject to the affirmative procedure – so would have to be voted on in both Houses – but the process is much simpler than for a fully fledged bill.

What are the drawbacks?

To allow the government to pass the necessary regulations in time, officials would need to have already identified all the relevant powers in existing legislation. But the bigger problem is where there is no existing legislation, meaning secondary powers cannot be used. For example, if the UK agreed to establish an independent regulator to assess proposals for state aid and make binding decisions that the government would have to follow, new primary legislation would likely be necessary (although the EU (Future Relationship) Bill does not appear to include specific provisions on this).

Option 2: pass an enabling bill

What does this involve?

To deal with these issues, the government could introduce a bill giving itself powers to implement a UK–EU agreement through secondary legislation. The bill would not implement it directly – though it could be used to bypass the CRAG process – but would allow ministers to pass regulations that did. This approach was partly used by the government in the Withdrawal Agreement Act.

Why might the government choose to do this?

This is the approach the government has taken in much of its Brexit legislation. It would ensure the government has the powers needed to implement all aspects of an agreement while keeping the bill short, simple and less vulnerable to amendment (though not totally immune). The lack of detail on what exactly the bill would do could make it less controversial with Brexiteer MPs, though the House of Lords has recently criticised the government’s use of high-level enabling bills that deprive parliament of the opportunity to scrutinise the legislation in detail.

What are the drawbacks?

The limited time available. Civil servants would need to analyse the deal in detail, work out precisely what changes need to be made to UK legislation to give effect to it, and then draft statutory instruments accordingly – and would not be able to lay them in parliament until the enabling act became law. Given there will only be a matter of hours between Royal Assent of the EU (Future Relationship) Bill and the end of the transition period, there will be very little time to pass statutory instruments in time for 1 January. Many will likely have to be passed using an expedited procedure, which provides for weaker parliamentary scrutiny.

Option 3: pass a bill to implement the agreement clause by clause

What does this involve?

The government could introduce a bill to implement each individual section of the agreement. This is the approach taken by many major trading nations. For example, when Canada signed its Comprehensive Economic and Trade Agreement (CETA) with the EU, its parliament had to pass a 'CETA Implementation Act'.

Why might the government choose to do this?

This would ensure that the entire agreement is implemented without having to identify what powers ministers already have in existing legislation. It could be simpler than Option 2 as the content of the implementing legislation would be concentrated in one bill rather than scattered across a bill and multiple SIs.

What are the drawbacks?

Limited time is once again a problem. In addition to the time needed by civil servants to analyse the deal and draft legislation accordingly (as in option 2), the government would likely need to allow more parliamentary time to debate a long and complex bill than it would for a shorter one (as in Options 2 and 4) – or at least would be under pressure to do so. The Canadian government had two years to draft the CETA Implementation Bill and parliament spent six months considering it. The government would have to ready the legislation as soon as the agreement was reached and then pass it before 31 December. Much would depend on the extent to which the government had already started drafting legislation to implement parts of the deal that are already broadly agreed.

The bill would also be amendable, which could cause problems if the government does not have a reliable majority for all elements of its agreement. Finally, if it turns out that the bill implements some aspect of the agreement incorrectly – and the rush to finalise it could make this more likely – it would be much harder to amend an act of parliament than an SI.

Option 4: pass a bill to give the agreement direct effect

What does this involve?

The government could pass a bill with a clause that directly incorporated the UK–EU free trade agreement (FTA) into UK law. This could use language similar to that in the European Communities Act 1972 (which provides for the incorporation of the EU treaties and other EU law) and the Withdrawal Agreement Act 2020 (which does the same for the Withdrawal Agreement). The FTA would be given direct effect and supremacy over any incompatible UK legislation.

Why might the government choose to do this?

A short bill declaring that the FTA had direct effect in UK law would be simple to draft, avoiding the need to analyse the deal in depth and work out what legislative changes were required. It would technically meet the requirement for implementing legislation to be in place before ratification, allowing the UK to ratify the agreement in good faith and in enough time before the end of the year.

What are the drawbacks?

Further legislation may still be needed to implement aspects of the agreement – for example, this approach would not by itself allow the government to set up a state aid control body.

This approach would also likely prove intensely controversial among hardline Brexiteers. While standard practice in countries such as the Netherlands, it is extremely rare for international agreements to be given direct effect in the UK: the EU treaties and the Withdrawal Agreement are the only key examples. Other treaties are implemented through some combination of Options 1, 2 and 3 and the government has said that this is also its intention for the other FTAs it is negotiating (such as with Japan). Using Option 4 for the EU FTA could imply that it is like the Withdrawal Agreement and not like the UK’s other FTAs – which some Conservative backbenchers may oppose.

Does the government have enough time to implement a deal?

It will only be possible to pass the EU (Future Relationship) Bill to implement the deal with the EU in time by significantly compressing the time available for parliamentary scrutiny. This is problematic and – as much of the Brexit legislation has shown – risks drafting mistakes that have to be corrected at a later date.

  1.  House of Lords Select Committee on the European Union, Uncorrected oral evidence: Progress of negotiations on the future UK-EU relationship, 7 October 2020,
Institute for Government

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