BASEL, Switzerland — UBS CEO Oswald Grubel resigned Saturday following a $2.3 billion rogue trading loss, a statement from the Swiss bank said.

In a statement, UBS said it was “deeply disappointed” by the scandal and that it regretted Grubel’s resignation.

Kaspar Villiger, UBS’s chairman, said, “Oswald Grubel feels that it is his duty to assume responsibility for the recent unauthorized trading incident. It is testimony to his uncompromising principles and integrity.”