According to the Financial Times article :"How the City finally raised its voice over Brexit",
Once the UK leaves the EU, it will leave the single market for goods and services and the City’s role as a hub for doing cross-border business with clients across the EU will have not legal grounds. Currently, 13 banks have already chosen Frankfurt or Berlin as their new EU hub, putting Germany in front in the race for City jobs. Dublin has attracted 12 groups — mostly banks but also a clutch of insurers and asset managers. Luxembourg, Belgium and the Netherlands are also set to win business.
More you will find on: https://www.ft.com/content/69764310-971f-11e7-8c5c-c8d8fa6961bb?utm_source=facebook