Home Secretary Jacqui Smith said the information needs to be stored in order to combat terrorism and other crimes. Critics have called the idea excessive and an infringement of civil liberites. Research from her department had estimated the proposal would cost up to 2 billion pounds to implement.

She stressed that the information from mobile phones and computers that might need to be accessed would be the 'who, when, where and how' of communications and not the content.

'My key priority is to protect the citizens of the UK, and communications data is an essential tool for law enforcement agencies to track murderers and paedophiles, save lives and tackle crime,' Ms Smith said in a statement.

'It is essential that the police and other crime-fighting agencies have the tools they need to do their job. However, to be clear, there are absolutely no plans for a single central store.'

In nearly all recent major counter-terrorism trials, prosecutors have used data about phone calls as part of their court case against suspects. Details about where calls were made, to whom and for how long have been used to show links between cell members and as evidence of preparation for an attack.

The government proposes legislating to allow all data that public authorities might need, including that generated overseas but crossing British networks, to be collected and retained by communication service providers (CSPs).

Opposition parties have strongly criticised the idea, saying officials had shown they could not be trusted with people's confidential information after a series of embarrassing data-loss scandals.

Civil rights groups say it would be a massive invasion of privacy.

'The big problem is that the government has built a culture of surveillance which goes far beyond counter-terrorism and serious crime,' said Conservative home affairs spokesman Chris Grayling. 'Too many parts of government have too many powers to snoop on innocent people and that's really got to change.' -- REUTERS