The chance of the UK leaving the European Union without a deal in place has increased significantly since the election of Boris Johnson to the roles of leader of the Conservative Party and Prime Minister in July. It is not a certain outcome of the current political crisis, but, given the obstacles which lie ahead of the Prime Minister as he seeks a deal with the EU that would be approved by parliament, it remains a very possible outcome. Even if the current Article 50 deadline of 31st October is extended as envisaged by the ‘Benn Act’ passed in September, the Conservatives will campaign at the anticipated general election on a platform of leaving the EU at the earliest opportunity, without a deal if necessary.

A good deal of analysis has been devoted to the implications of a disorderly Brexit for the supply chains that deliver food, medicines and other vital goods to UK consumers, and to the short and longer term economic shocks which may ensue. But much less consideration has been given to what no deal might mean in political and legal terms for the domestic Union, and whether – and how – the UK might break apart as a result.

This briefing paper addresses this gap. It explores some of the main potential ramifications for the territorial politics of the UK of exiting without a deal in place with the EU, and identifies some of the key flashpoints and future events that will shape the politics of the coming period.