Britain's top banks are drafting in staff for Brexit all-nighter after EU referendum
![Britain's top banks are drafting in staff for Brexit all-nighter after EU referendum](http://i.dailymail.co.uk/i/pix/2016/06/19/16/01308A1B00000578-0-image-a-53_1466349463060.jpg)
Barclays, Lloyds Banking Group and US giants such as JP Morgan Chase and Citi are among those drafting in workers for what is set to be a turbulent 24 hours after voting closes at 10pm