Zurich: Swiss banking giant UBS announced on Saturday that Chief Executive Officer Oswald Gruebel has handed in his resignation, which was accepted by the board of directors, in the wake of a trading scandal.

Sergio Ermotti has been named as interim CEO effective immediately, a bank statement said, nine days after the arrest of a trader accused of a USD 2.3 billion fraud at UBS.

While the board "regrets" Gruebel's decision UBS Chairman Kaspar Villiger said in the statement Gruebel "feels that it is his duty to assume responsibility for the recent unauthorized trading incident."

Villiger praised Gruebel for "his uncompromising principles and integrity", and acknowledged that during his tenure "he achieved an impressive turnaround and strengthened UBS fundamentally."

The board also said it would "fully support" the independent investigation into the rogue trading and would ensure that "mitigating measures" were implement to prevent such incidents from recurring.

Kweku Adoboli, 31, the trader accused of the massive fraud at UBS' London offices, is "sorry beyond words" over the losses, his lawyer said on Thursday, as a court remanded him in custody for another month.

(Agencies)