The security services are gaining access to an unprecedented amount of personal detail on British citizens, privacy campaigners have warned.

Watchdog organisation Privacy International said that up to a billion pieces of individual information had been handed over to government agencies.

The organisation, which has launched a campaign to help UK consumers retrieve the information that is held about them, warned that modern technology was providing increasingly detailed information available to the government.

Compiling new figures from a variety of official and industry estimates, Privacy International said that the police and other investigative agencies were now making around a million requests a year for telephone billing data, email logs, personal details of customers and records showing the location where mobile phone calls were made.

These requests involve an estimated 100 million individual phone calls, subscriber data on nearly a million consumers and the acquisition of an unknown number of email and internet logs.

Privacy International director Simon Davies said the estimates were "very much on the low side" and did not include access to email or internet activity, or investigations by security organisations such as GCHQ.

"We literally halved the Home Office estimate before commencing the extrapolation, just to be on the safe side" he said.

Information including credit card numbers, dialled phone numbers, websites visited, television programmes watched and personal financial data can be monitored and recorded.

The data can be combined into a comprehensive dossier on the contacts, friendships, interests, transactions, movements and personal information on almost everyone in the UK, warned campaigners.

BT stores records for up to seven years and these are sent automatically on request to government agencies without the need for human intervention, said Privacy International.

And mobile phone providers are able to provide authorities with information on their customers' geographic movements, while using their phone, going back months and sometimes years.

"We see the current arrangement as a collusion of interests that will ultimately expose the most intimate details of people's lives" said Davies.

He called on both government and companies to respect the privacy rights of customers.

The exercise of data protection rights will "send a clear signal to communications providers and to government that people have a high regard for their right to privacy", he added.