The e-mail, which was sent by the human resources department to all 1300 employees of the insurance firm's asset management unit, told recipients to clear their desks and return all of the company's property on their exit.

Aviva announced plans to downsize its Investment arm in January, as the business feels the squeeze from the sovereign debt crisis in the Eurozone. At the time, the firm said it would release 160 employees as part of the restructuring.

A spokesperson for Aviva put the mass firing down to a clerical error in the human resources department, saying that the e-mail should have been sent to one member of staff only.

Just two days earlier Aviva had announced the departure of Alain Dromer, head of Aviva Investors, as part of a management overhaul intended to introduce a new "flatter organisation...result(ing) in shorter and more direct reporting lines".