UBS chief executive Oswald Gruebel has resigned over a $2.3 billion loss caused by rogue trading at its investment division, which is to be restructured now to prevent similar incidents in future, the Swiss bank said Saturday. Gruebel, who had come under heavy pressure from shareholders over the scandal, said he hoped his resignation would allow the bank to restore its reputation in the eyes of clients and investors. Article Controls EMAIL REPRINT NEWSLETTER SHARE "As CEO, I bear full responsibility for what occurs at UBS ( UBS - news - people )," he said in a memo to staff. "From my first day on the job I placed the reputation of the bank above all else. That is why I want to and must act according to my convictions." UBS Europe chief Sergio P. Ermotti will take over immediately as interim chief executive until Gruebel's replacement is appointed. Gruebel's departure caps 10 days of speculation over his future following the bank's announcement that a single London-based trader had evaded internal control systems and gambled away $2.3 billion. The trader, 31-year-old Kweku Adoboli, was arrested Sept. 15 and charged with fraud and false accounting. A judge ordered him Thursday to be held in jail until a hearing next month.