If Britain decides to leave the EU in its June 23 referendum, it would set off one of the most complicated divorces in history. How the break-up is negotiated and carried out would have a decisive impact on the country’s economy and place in the world for generations. Here is a taste of the formidable To Do list that would confront British officials and politicians if Brexit took place.

Money Settle outstanding EU bills. Contributions to 2017-2020 budget expected to be £56.6bn gross and £26.3bn net. Partition share of debts to EU institutions. Sort future pension promises made to eurocrats.

Free movement Agree residence and residual work rights for 3m EU-born UK residents and some 1.8m British passport holders in EU countries. Establish rights for their family members, and future cross-border workers.

Corporate rights Establish rights for UK and EU companies with cross-border affiliates. Clarify contractual obligations, access to courts, and investor rights.

Regulations Renationalise 5,896 full EU regulations and 6,399 technical regulations by ditching them, passing legislation or negotiating a transition. Such regulations currently directly apply to the UK, but are not on the UK statute book.

Directives Renationalise EU directives by adjusting or repealing Brussels-inspired law to adjust to new priorities or adapt to Britain’s new relations with the EU. At least 15 per cent of the UK statute book is based on 978 EU directives and 656 related technical directives.

Trade Renegotiate or reconfigure deals with more than 50 countries. The UK has not independently concluded such an agreement since the 1970s.

Air transport Britain potentially loses rights under 78 EU-negotiated agreements. New landing and airport access rights must be agreed with the EU and scores of international governments.

Enforcement National bodies replacing EU agencies need funding, manpower and legal clout to replace EU agencies. This covers competition, trade agreement and protection, farming, pharmaceuticals, chemicals and food safety standards.