The departure of Melanie Gee brings to 20 the number of senior executives to have left UBS investment bank in the last 14 months. Exits have come across all divisions of the investment bank as executives resigned to join rivals or fell victim to reshuffles intended to boost the ailing fixed income business.

The bank's North American business was rocked last year by the resignation of Ken Moelis, president of the investment bank who left after a disagreement with the bank’s Swiss management. Several executives followed Moelis out of the door.