The Financial Services Authority (FSA) and the Swiss Financial Market Supervisory Authority (FINMA) have commenced a formal enforcement investigation against UBS concerning unauthorised trades made by Kweku Adoboli.

The regulatory bodies confirmed that they are in close contact as they conduct an investigation into the losses racked up by rogue trader Adoboli at the investment firm last year.

He was found to have lost around £1.5 billion through unauthorised trading in the London operations of its investment bank.

The Swiss regulator and the FSA announced the joint launch of an independent investigation into the scandal on 16 September 2011.

In a statement, FINMA said it has now initiated formal administrative enforcement proceedings against UBS under Swiss law.

The regulatory body continued, ‘FINMA will assess and rule upon the adequacy of the controls that were in place to prevent and detect unauthorised trading within the investment bank and their compliance with the Banking Act and the Stock Exchanges and Securities Trading Act and related regulations.’

Adoboli pleaded not guilty to two charges of false accounting and two of fraud when he appeared at Southwark Crown Court at the end of January.

He worked in the group’s global synthetic equity business at its London office.

A provisional trial date has been set for 3 September 2012.