The private correspondence of millions of people who use social networking sites could be tracked and saved on a “big brother” database, under new plans being drawn up by the UK government.

Ministers revealed yesterday that they were considering policing messages sent via sites such as MySpace and Facebook, alongside plans to store information about every phone call, e-mail and internet visit made by everyone in the United Kingdom.

There was immediate uproar from opposition parties, privacy campaigners and security experts who said the plans were over-the-top and unworkable.

There have long been proposals, following an European Union directive in the wake of the July 2005 bombings in London, for emails and internet usage to be tracked in order to guard against future terrorist attacks.

But since then, social networking sites have exploded in popularity, with around half the British population thought to be using them. Security services fear that this is a loophole that terrorists and criminals could exploit.

Vernon Coaker, the Home Office minister, has revealed that social networking sites may be forced to keep information about how their members are using their sites.

"Social networking sites, such as MySpace or Bebo, are not covered by the directive," he said.

"That is one reason why the Government is looking at what we should do about the intercept modernisation programme because there are certain aspects of communications which are not covered by the directive."

The government insists that the contents of each message would not be collected, but that the data on exactly who each person had corresponded with would be tracked and eventually logged on the database.

The move has been met with fierce criticism. Liberal Democrats Home Affairs Spokesman said: “"We need complete clarity from the Government over what data they will retain and how it will be kept secure.

"Will membership of Facebook groups or people listing 'suspicious' interests be caught in their dragnet?

"We also need guarantees that the Home Secretary's 'Dustbin Stasi' won't use terrorism legislation to access retained Facebook data for frivolous purposes, such as identifying people who let their dogs foul the pavement."

Others suggested that the government’s planned “big brother” database was becoming so large and ambitious in scope that it could never be fully secure.

Michael Parker, spokesman for campaign group NO2ID, said: “Their plans for the intercept modernisation programme were completely unworkable to begin with and are becoming more so with every addition they suggest.”

Rik Ferguson, a security expert at Trend Micro, the internet security firm, said: “The Home Office insists that this information is vital for fighting crime and terrorism; but is this legislation really going to be effective against the people at whom it is supposedly aimed?

“If national governments and law enforcement organisations truly believe that online criminals and international terrorists don’t know how to hide their online traces, then we have a bigger problem than we thought.”

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