Britain said on Thursday it would rush through emergency legislation to force telecoms companies to retain the data of users for a year, saying the move was vital to protect national security following a decision by Europe's top court.
Communication companies had been required to retain data for 12 months under a 2006 European Union directive which was thrown out by the European Court of Justice in April.
The scrapping of the directive could deprive police and intelligence agencies of access to information about who customers contacted by phone, text or email, and where and when, the British government said.
British Prime Minister David Cameron said the emergency legislation would restore this capability and enshrine it in law, ensuring investigations would not be hampered and giving protection to the telecom firms from possible legal challenges.
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However, he stated the measure would not give the authorities any new powers to access Britons' personal data or the content of their calls or emails, a hugely controversial issue which has already led to one proposed law being ditched in the wake of privacy concerns.
"No government introduces fast track legislation lightly. But the consequences of not acting are grave," Cameron said in a statement.
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"I want to be very clear that we are not introducing new powers or capabilities - that is not for this Parliament. This is about restoring two vital measures ensuring that our law enforcement and intelligence agencies maintain the right tools to keep us all safe."
The emergency security legislation, which has the support of all three major parties, will include a termination clause meaning it will expire in 2016 meaning lawmakers will have to look at the measures in detail again before then.
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