Some Tories (whose home-affairs spokesman, David Davis, claims to have warned Mr Brown, also in December, of a violation of the Wilson doctrine, though without naming Mr Khan) question Mr Straw's grip on his department.

ECONOMIST: Britain's web of surveillance ensnares an MP

It lost its negotiating grip over the health department when Tony Blair committed the government to an enormous boost in spending on health.

ECONOMIST: Public spending

MPs also rebuked the department for not getting a grip on spending across Whitehall, and "impenetrable" book-keeping.

BBC: Treasury attempts to boost lending have 'failed', MPs say