Brexit briefing: it’s not just Article 50, it’s Article 218, too

For all the talk about Article 50, which U.K. Prime Minister Theresa May will formally trigger to begin exit negotiations next week, Britain’s post-Brexit future will be shaped to a far greater extent by another provision of the EU treaties: Article 218.

While Article 50 governs a country’s departure from the bloc, Article 218 describes how the EU makes agreements with “third countries or international organizations.” So while Article 50 will get the U.K. out the door — the indisputably crucial first step — experts on EU law say an agreement on the future relationship between the U.K. and the EU can only be brokered under Article 218, once Britain returns to third country status.

In declaring that its chief Brexit negotiator, Michel Barnier, will not have a mandate to negotiate a trade deal or other future agreement, Brussels is clearly seeking some tactical advantage, trying to force resolution of divorce issues like the U.K.’s post-Brexit financial obligations and the rights of citizens. Only if Barnier brings the EU27 a satisfactory result on that front, officials say, will leaders consider broadening his mandate to include a future trade deal or other partnership agreement.

But it’s not merely a strategic ploy. The EU is also declaring what its lawyers understand to be legal fact. Any withdrawal deal with the U.K. that violates the terms of the EU treaties would be subject to invalidation by the European Court of Justice.

While the approach may seem overly legalistic in what is certain to be a highly political negotiation, legal technicalities can cut both ways. For instance, the two-year deadline for a withdrawal agreement set in Article 50 was actually designed, experts say, to benefit a departing country by making sure it could not be held hostage.

Article 50 requires only a qualified majority of EU countries to approve a withdrawal agreement, while a future trade deal will likely require unanimity. While the U.K. has yet to clarify its own wish list for a future relationship, this much is clear: Treaties are what make the EU the EU. And if Brexit is about reclaiming independent, third-country status, there may be no more important provision for the U.K. going forward than Article 218.