Britain's foreign minister used an international gathering of defence officials in Germany on Friday to call for closer global cooperation in improving cybersecurity.
"Cyberspace is changing the way we view and conduct foreign policy as well as transforming our everyday lives," William Hague told the Munich Security Conference.
"But there is a darker side to cyberspace that arises from our dependence on it."
He said the Internet helped undemocratic governments repress their citizens, gave "hostile" nations new channels to steal secrets and helped "terrorists" and criminals.
"In Britain we believe that the time has come to start seeking international agreement about norms in cyberspace," he said.
"Cybersecurity is on the agendas of some 30 multilateral organisations... But much of this debate is fragmented and lacks focus."
Britain is prepared to host an international conference later this year on the subject.
"We do not underestimate the difficulties ahead. Many countries do not share our view of the positive impact of the Internet, and others are actively working against us in a hostile manner.
"However as liberal democracies we also have a compelling interest in supporting democratic ideals in cyberspace, and working to convince others of this vision."
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