The coalition government has torn up figures that pegged the cost of plans by the intelligence services to store records of every online communication at £2bn.
A Home Office spokesman told The Register that the previous government's estimate of the cost of the Interception Modernisation Programme (IMP) has been abandoned.
He declined to provide a revised figure, saying new proposals for internet surveillance will be announced in November. This raises the possibility either that suggestions by industry sources that the original estimate was unrealistically low were correct, or that the scheme is being scaled back.
The spokesman flatly denied claims in The Guardian that access to IMP data would be restricted to "terror-related" investigations, however. Communications data is vital to all law enforcement, he said.
Home Office officials have been working on IMP for more than three years. It aims to capture communications data - the whom, when and where of communications - from the array of third-party services that use the internet, including Facebook, Gmail and Skype.
In the most likely scenario, ISPs will be compelled to capture such data as it passes over their networks and store it in very large databases. The intelligence services and police would then be able to access these silos with the authorisation of a senior officer, as they currently do with basic session data.
It would require thousands of Deep Packet Inspection probes to be inserted throughout the UK's internet infrastructure, and for them to be constantly reconfigured, very probably by GCHQ, to keep up with changes in how services exchange communications data. The scale of the challenge last year drew doubt from the industry over the cost estimate of £2bn over 10 years, and the Home Office never explained how it arrived at the figure.
After almost a year of pre and post-election silence, IMP reemerged last week as part of the Strategic Defence and Security Review, to the surprise of some, including relevant industry figures who had previously been notified on progress.
A little-read Home Office document from July had already indicated the plan was never off the agenda. It said the coalition would "publish proposals for the storage of internet and email records, including introducing legislation if necessary".
That quiet announcement was made weeks after David Cameron and Nick Clegg had told voters they would "end the storage of internet and email records without good reason".
Their intention to introduce legislation "if necessary" also represents a shift in position. In April last year, when Labour was bringing the European Data Retention Directive (EUDRD) into UK law, Baroness Neville-Jones, who is now security minister, criticised any parallel attempt to bring in IMP without primary legislation.
"Are we going to get any primary legislation?" she asked.
"The government would do well to come clean on their intentions, since failure to do so obliges one to examine the scenarios that could develop without primary legislation."
Her brief at the Home Office today includes IMP, and a spokeswoman today declined to say whether primary legislation will be proposed. Unlike a statutory instrument, such as the significantly less invasive EUDRD, primary legislation requires full debate in both Houses of Parliament. ®