Barclays sent some staff home from its London trading floor after two employees tested positive for Covid-19, in another example of the potential pitfalls large banks face as they ramp up the return to the office.

"Earlier this week, two colleagues based on level 2 of 5 North Colonnade received this confirmation" of having contracted the virus, Barclays' head of markets Stephen Dainton wrote in a memo sent to employees on 2 September. The North Colonnade building in Canary Wharf houses the Barclays investment bank and trading floors.