DIMON: JPMorgan could move some of its 16,000 UK jobs to Europe in the event of a Brexit

JPMorgan could move an undisclosed number of its 16,000 UK-based staff to Europe if Britain votes for a Brexit in the June 23 referendum, the bank's CEO Jamie Dimon said in a speech on Friday.

Dimon added in his speech, which was delivered to the bank's staff in Bournemouth, Britain, that "if the UK leaves the EU, we may have no choice but to re-organise our business model here."

JPMorgan opened in Britain 150 years ago and now employs 16,000 people across six sites - Basingstoke, Bournemouth, Edinburgh, Glasgow, London, and Swindon.

The Bournemouth site, where Dimon delivered his speech to employees alongside UK Chancellor George Osborne, employs around 4,000 people, including over 1,300 technology specialists. Those 4,000 staff make JPMorgan the largest private sector employee in Bournemouth.

Dimon added that "we love being in the UK because you've got everything we want: the high calibre talent, the language, the culture, and the history."

Here are other key passages in his speech:

We mostly know what it looks like if Britain stays in the European Union: It's effectively, a continuation of a more predictable economic environment.

But the range of outcomes of a Brexit is large and potentially unknown.

We'd need to see what happens in the following weeks and months if the UK votes to leave. We can't wait for ever, because we will need to make decisions quickly to do what is right for our clients and our JPM colleagues.

At the end of the day, that's who we have to serve and support. One realistic outcome is that we lose the ability to passport our banking and trading services into Europe. But our clients will still need us to trade within what will then be the EU. If that's what the rules say, we will need to do what works.

So if the UK leaves the EU, we may have no choice but to re-organise our business model here. Brexit could mean fewer J.P. Morgan jobs in the U.K. and more jobs in Europe.

My observation of the facts is that a vote to leave would be a terrible deal for the British economy. At a minimum, a Brexit will result in years of uncertainty and I believe that this uncertainty will hurt the economies of both Britain and the European Union.

In a bad scenario, and this is not the worst-case scenario, trade retaliation against Britain by countries in the European Union is possible, even though this would not be in their own self-interest. Retaliation would make things even worse for the British and European economies. And it is hard to determine if the long-run impact would strengthen the European Union or cause it to break apart.

Britons vote on whether to stay within or leave the European Union on June 23.