Upcoming rules that force internet companies to hold details of every e-mail sent in Britain are a waste of money and an attack on privacy, according to a prominent security expert.

From March, all internet service providers (ISPs) will have to keep data about e-mails sent and received in the UK for a year. The content of individual e-mails will not be kept by the authorities, but the timing and number of each communication will be stored.

At the moment, a similar database of telephone records - fixed and mobile - is held by telephone companies. The implementation of an EU directive, agreed after the alleged plot in August 2006 to set off bombs aboard transatlantic airlines, will extend the information available to the Government to include e-mail and internet traffic.

The Government will reportedly have to pay the ISPs more than £25 million to ensure the law is obeyed.

But Dr Richard Clayton, a security researcher at the University of Cambridge's computer lab said the costs of the regulation could have been better spent.

"There's going to be a record of every single e-mail which arrived addressed to you and all the e-mails you sent out via your ISP,” he told the BBC. “That of course includes all the spam."

Opposition parties have also criticised the move. The Earl of Northesk, David Carnegie, a Conservative peer on the House of Lords Science and Technology Committee, said the proposals meant anyone's movements could be traced 24 hours a day.

"This degree of storage is equivalent to having access to every second, every minute, every hour of your life. People have to worry about the scale, the virtuality of your life being exposed to round about 500 public authorities.

"Under Article 8 of the European Convention on Human Rights, privacy is a fundamental right. . . it is important to protect the principle of privacy because once you've lost it it's very difficult to recover."

The Home Office said the data would be useful for combating crime.

A consultation paper to be published by the Home Office within the next few months will outline a range of options for updating storage arrangements including everything being held on a huge Government database or asking the private sector to hold it in one place.

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