JPMorgan Chase's Synthetic Credit Portfolio included the 'London Whale' trades Getty

The City's main regulator has fined the former head of CIO International at JPMorgan Chase £792,900 for his role in the 'London Whale' trades. The chief investment office (CIO) chief, Achilles Macris, was responsible for the trades' portfolio in 2012.

The Synthetic Credit Portfolio included trades by Bruno Iksil, one of the most renowned traders of recent years, often referred to as the 'London Whale' because of his sizeable trades, and also dubbed 'Voldemort' because of his authority in the City.

Iksil is alleged to have caused JPMorgan Chase to lose $6.2bn (£4bn, €5.5bn) by betting on the creditworthiness of companies, but the Financial Conduct Authority (FCA) dropped the probe into his alleged misconduct.

Macris, who worked as Iksil's boss and was the FCA's main contact in the case called an 'approved person', has now been fined because of his communications failures with the regulator. The CIO chief failed to communicate concerns about the Synthetic Credit Portfolio specifically, despite his obligations as approved person.

"A failure to communicate openly with us can affect the well-running of markets and cause unnecessary harm to investors, especially in times of financial stress or crisis. Regulators need open communication with firms so that better decisions can be made sooner," FCA enforcement director Mark Steward said. "Mr Macris should have explained the position more squarely especially when he knew the Synthetic Credit Portfolio's losses had worsened."

The FCA ruled that Macris was given the opportunity to come clean about concerns, such as increased losses and the troubled position of the Synthetic Credit Portfolio. When the finance tycoon was already aware of the problems in the division, he allegedly said there was no cause for concern in scheduled phone calls with the FCA.