The UK's treasury chief Tuesday said he was "profoundly concerned" by the irregular release of market-sensitive information by the markets regulator last week, and instructed its chairman to instigate a "thorough" and "objective" review as soon as possible.

But Chancellor of the Exchequer George Osborne stopped short of granting parliamentary demands for an external inquiry into the affair. Andrew Tyrie, head of the committee that monitors financial services on behalf of the House of Commons, had said the Financial Conduct Authority "mustn't be allowed to investigate itself".