The row erupted after the UK's head of immigration removals David Roberts told MPs on Tuesday he did not "have the faintest idea" of the numbers.

BBC: NEWS | UK | UK Politics | Blair 'rattled' over immigration

Or to put it another way, if you have the faintest idea how to turn the Big Four into the Not-Quite-So-Big Eight, with consequential benefits to the cost and quality of audits, I know a watchdog desperate to hear from you.

BBC: Can the stranglehold of Big Four auditors be broken?