A former colleague of Kweku Adoboli on the exchange-traded funds desk at UBS today said he was just “sounding off” when a court heard how he had complained about trading limits.

John Hughes, who is a witness in the criminal case against Adoboli, today faced a fourth day of cross examination from Adoboli's defence lawyer. Adoboli is accused of two counts of fraud and two of false accounting in a $2.3bn unauthorised trading scandal. He denies the charges.