How can the government minimise the loss of business to the City, and tax revenues to the Treasury, from Brexit?

Most obviously, it needs to secure the best possible deal for the City during eventual negotiations over the future trading relationship with the EU27. More generally, it must also ensure that London remains the most attractive place to carry out global financial services. In addition, it could use financial regulators to make it difficult for companies to shift activity out of the UK. This last option, however, would be a mistake.