Stewart Ford is planning to sue the Financial Conduct Authority (FCA) for £370m, five years after his company, Keydata Investment Services, collapsed.

According to a report in The Independent, Ford plans to take legal action against the financial regulator as he believes that the FCA, which worked as the Financial Services Authority (FSA) at the time, intentionally pulled the plug on his business for the FCA's own benefit.

The official reason given by the watchdog for cutting off Keydata was because it had run up huge debt, and an unexpected £5m tax bill was the final nail in the coffin for the investment firm.

However, Ford believes that the FCA went after him and his company "to promote some benefit to the public at my expense".

"The purpose was to demonstrate the effectiveness of the FSA as a 'robust' regulator in the wake of the financial crisis of 2008, and thus restore public confidence in the FSA," he said, in an eight-page letter to the FCA.

Keydata went into administration in 2009, putting around 30,000 investors at risk of losing a combined £450m.

Ford felt that the company was profitable until it was "ambushed" by the regulator, and he says that it was close to agreeing a deal with HMRC over protecting the Isa status of investors.

Ford believes that his personal investment in the business was worth up to £100m and he also feels that the FCA has caused massive financial losses and "grievous and irreparable harm" to his reputation.