David Strachan, the director of financial stability at the Financial Services Authority (FSA), has resigned.

In an internal email to FSA staff Hector Sants, the chief executive of the FSA, said Strachan would stay at the regulator until early next year before joining Deloitte, a financial services firm, where he will be co-head of its centre for regulatory strategy in Deloitte's risk and regulatory practice.

Strachan's departure follows the resignation of a number of high-profile directors at