The UK government would be foolish not to appoint an EU commissioner if Brexit is delayed

Ursula von der Leyen, the incoming European Commission president, has announced the 25 commissioners who will be joining her and the high representative, Josep Borrell, at the head of the next European Commission. They will now face hearings in the European Parliament and, if confirmed, will begin their work on 1 November.

There was no British nominee. The UK government has said the UK’s scheduled departure from the EU on 31 October means it would not propose a British commissioner. But with the government now legally required to seek a Brexit extension if Parliament has not approved an exit on 31 October, the possible absence of a UK commissioner is being questioned.

EU law requires the UK to appoint a commissioner if it is an EU member

Von der Leyen’s view is that the UK would need to appoint a commissioner if Brexit negotiations were extended past the 31 October. Article 17 (5) TEU of the Lisbon Treaty removed that obligation, saying that any new Commission must have members from at least two thirds of EU countries. But, before the treaty came into force, member states had already decided to revert to the old process of appointment and insisted that any Commission must have a member from every EU country. This was turned into a legally binding decision in 2013, meaning that the UK would be required to appoint a commissioner if it were still a member state past November. But the penalty for non-compliance would be an infringement procedure against the UK, not expulsion from the EU.

The EU and the UK could decide to make an exception due to Brexit uncertainty

EU and UK leaders could decide to make a derogation for the UK under Article 17 (5) TEU and allow the UK to continue being a member state without having to appoint a commissioner. But this would require the consent of all member states – including the UK. Likewise, the EU could refuse a British request not to appoint a British commissioner. But there are reasons to believe it would make an exception – not least to prevent complications in the process of approving the new Commission in the autumn.

The UK should really appoint an EU commissioner if there is a delay to Brexit

However, the government would be foolish to renounce its right to appoint – even if its commissioner was only in post for the proposed four-month extension. The first weeks of any incoming Commission are busy: it is the chance for commissioners to table new and innovative proposals, as well as meet with the European Parliament and EU leaders to discuss what they would like the EU to achieve. It is the time when the new Commission turns the big themes into a detailed work programme – which will also set some of the parameters for the UK’s future relationship with the EU. A UK commissioner would get first-hand information on the new European Commission and its plans.

Building close relations with those at the top of EU institutions can come in handy after Brexit

But it is not just the substance that matters. Having a UK commissioner will help start to build the personal relations with the new Commission team and their staff – meeting the people who call the shots and have behind-the-scenes influence, as well as observing how the new Commission functions. That is much harder to build from the outside – which is one reason why the decision to step back from EU working groups is so short-sighted. Insider knowledge is vital currency in Brussels, and building those working-level contacts could come in very handy once the UK has left the EU.

Refusing to assign an EU commissioner would send a strong political message that the UK will be leaving the EU – but the UK government would be wise to agree with Von der Leyen's insistence to appoint a British commissioner. It is a move which will pay off in both the immediate and long term.