Ministers are preparing a major expansion of the Government's powers to monitor the email exchanges and website visits of every person in the UK, according to reports.
Under legislation expected in next month's Queen's Speech, internet companies will be instructed to install hardware enabling GCHQ - the Government's electronic "listening" agency - to examine "on demand" any phone call made, text message and email sent, and website accessed in "real time", The Sunday Times reported.
A previous attempt to introduce a similar law was abandoned by the former Labour government in 2006 in the face of fierce opposition.
However ministers believe it is essential that the police and security services have access to such communications data in order to tackle terrorism and protect the public.
Although GCHQ would not be able to access the content of such communications without a warrant, the legislation would enable it to trace people individuals or groups are in contact with, and how often and for how long they are in communication.
The Home Office tonight confirmed that ministers were intending to legislate "as soon as parliamentary time allows".
Nick Pickles, director of the Big Brother Watch campaign group, said: