Legislation aimed at giving Europeans greater control over the electronic storage of their personal details takes effect this weekend.

BBC Internet Correspondent Chris Nutall: Good news for citizens - not so good for business

The European Data Protection Directive is being welcomed by individuals and civil liberties groups.

But businesses face massive problems meeting its requirements and the United States is concerned at the consequences of its own inability to match the standards.

The directive was adopted in 1995 and gave the 15 member states of the European Union three years to bring their own legislation into line.

BBC Internet Correspondent Chris Nutall reports

By the deadline at midnight on Friday, only the UK, Greece, Italy, Portugal and Sweden were in proper compliance.

The new laws say personal data can only be collected if an individual consents and they must be told how the information will be used.

They must have access to the data and be able to correct or erase it.

The regulations seem likely to cause direct marketing companies and the online industry the most problems.

They rely on easy access to personal data to target products and offer personalised services.

'Industry should regulate itself'

The United States views the directive as the biggest threat to the growth of electronic commerce. It believes industry should regulate itself and its privacy legislation falls short of the standards demanded by the directive.

In theory, this could block the transfer of data between the United States and Europe under the new laws, thwarting the development of e-commerce by American companies.

In practice, this seems unlikely to happen in the short term, with talks going on between the US Commerce Department and the European Commission, and many EU countries still not in line with the directive.

But pressure groups are promising to pursue the proper implementation of the directive.

Privacy International says it will go to the courts if necessary to see it enforce it.

Already the group is targeting 25 agencies and multinationals from the Federal Bureau of Investigation to Coca Cola, American Express and Microsoft.

It wants them to reveal their internal privacy mechanisms and the nature of their data flows outside Europe.