Article 50 and Brexit – an explanation

That means that despite the Brexit majority in the 23 June referendum, it could be September before Britain invokes Article 50 of the Lisbon Treaty – the legal instrument under which a nation can serve notice that it intends to leave the EU.

To the frustration of Jean-Claude Juncker, the European Commission president who has called for an “immediate” start to withdrawal negotiations, only the national government of a leaving nation can nominate the date that triggers the Article 50 procedure, which provides a two-year window for the EU and the departing country to agree, if possible, new arrangements for everything from trade to the movement of labour.

Whether or not two years – during which the UK will remain an EU member –is long enough to reach such a comprehensive deal is open to doubt. Some experts predict it could take eight or even ten years to complete and, indeed, the remaining members of the EU can extend the two-year period, but only if all 27 remaining members agree.

Germany’s Chancellor Angela Merkel insisted on Tuesday that the UK would not be allowed to “cherry pick” the parts of its EU membership it wants to keep post-Brexit and said that, if it wanted continued access to the free trade area, it would have to accept the free movement of labour – the rejection of which was a key plank of the ‘leave’ campaign in the referendum.