UK AND EUROPE. IMPLICATIONS FOR THE PARIS AGREEMENT ON CLIMATE

One question that may arise in the UK’s referendum debate is the effect of EU membership on the continuing force of the Paris COP 21 agreement, if the UK votes to leave the EU. Will the UK still be bound by the agreement if it leaves? The answer, unsurprisingly perhaps, is relatively simple to state but perhaps more complex in practice.

First, both the EU and the UK separately became signatories (link provides a full list) on 22 April 2016, among 175 parties signing on that day. This in itself is a surprising story, with a previously recalcitrant Russia as one of the signatories, but not Saudi Arabia. The EU’s internal decision making processes are complex and the official Council decision authorising the EU signature to the Paris agreement was only published on 19 April.

It is likely that there will be significant further internal negotiation before the EU is able to ratify the agreement. Definition of competence is relevant here. In "economic" areas such as trade in goods and the internal market the EU has exclusive competence, but in areas such as environment and climate, competence is shared with member states. In these areas they conclude "mixed agreements" – where both EU and individual member states sign. But in any case significant negotiations are likely to be involved. It is unlikely that the EU would be able to sign up to a commitment without a clear understanding of how it would impact on the individual member states.

Prima facie the position is very simple. If the EU signed an agreement and the UK or any member state subsequently left, then that state would not be bound by the agreement unless it had also signed the agreement itself. If it had not signed it would not be so bound. If it had signed and the EU had not, it would also be bound.

At present it may seem unlikely that either the EU or the UK will ultimately fail to ratify the agreement before the date set for UK exit from the EU after triggering Article 50 of the Treaty on European Union. However given the political correlation between scepticism over Europe and over climate policies, it is possible that the EU could ratify and the UK could leave before ratification, and that the UK could refuse to ratify. The converse, the UK ratifying while the EU did not, currently seems much less likely, but cannot be ruled out if other tensions within the EU continue to multiply.

If, as seems most likely, the momentum from Paris continues to grow, a failure to ratify could make life very difficult for the UK in future post Brexit trade negotiations both with the EU and with other countries. If this is appreciated by ministers, the possibility of non-ratification may seem a little academic.