Chuck Prince resigned as chairman and chief executive of Citigroup after the bank revealed pre-tax losses in its sub-prime mortgage-related holdings of between $8bn (£3.8bn) and $11bn. Financial Times, The Times, Daily Telegraph, Independent.

Former US Treasury secretary Robert Rubin will take over as chairman and Sir Win Bischoff, former head of Schroders and now chairman of Citi Europe, will be temporary chief executive.

Citi said the further writedown reflected a series of rating agency downgrades of sub-prime related assets and “other market” developments since the end of the third quarter.

Prince said that “given the size of the recent losses in our mortgage backed securities the only honourable course for me to take as chief executive officer is to step down”.

Prince resigned at an emergency board meeting which had been called to consider his future and further losses the company faces as a result of the sub-prime mortgage crisis.

Citi recently announced $1.6bn of losses on its mortgage-backed securities for the third quarter, which prompted the departure of several senior executives including Tom Maheras, head of all Citi’s capital markets operations.

But the value of mortgage securities packaged into collateralised debt obligations has fallen further in recent weeks sharply increasing the losses Wall Street banks face.