Commerzbank's former top US banker has returned to the financial markets after a three-year hiatus, emerging as joint head of mergers and acquisitions at a London-based independent investment bank.

Omar Bayoumi, who was head of Commerzbank's capital markets and advisory business in London before switching to become chief executive of the German bank's US securities subsidiary in April 2003, has been out of the investment banking industry since quitting Commerzbank in September 2004.