Herbert Smith Freehills will go up against private client boutique Harcus Sinclair as thousands of investors in Lloyds Banking Group prepare a class action-style lawsuit claiming the 2008 government takeover of HBOS left them £400m out of pocket.

The original claim launched by a group of around 200 investors has now been joined by more than 5,000, who allege that they were kept in the dark about emergency support packages the bank received from both the Bank of England and the US Federal Reserve.