The review will seek public submissions for the next month and will then hold a series of public and classified hearings. Illustration: Simon Letch ''It will be one of the most controversial inquiries the committee has ever held,'' a government official speaking on condition of anonymity said. ''Once people get their head around this stuff it will be very interesting to see what their reaction will be. In the UK it has led to some very vocal opinions.'' A similar data retention regime proposed in Britain - though of only 12 months, rather than two years, duration - has been widely debated and England's Information Commissioner, Christopher Graham, has stated the case for such regimes has yet to be made.

The Australian proposals will also be sure to attract strong criticism from the Greens and civil liberties groups. The discussion paper outlines changes to the various Acts governing Australia's six intelligence agencies - which include ASIO, ASIS and the Defence Signals Directorate (DSD). They are also divided into three categories - those the government agrees with, those they are considering, and those they are seeking advice on. The proposed reform likely to cause the most outrage is the intention to force all telecommunications providers operating in Australia to retain users' data for up to two years. While some companies voluntarily retain data for such periods, others delete users' call records and internet usage data almost as quickly as they receive it. Such data retention schemes have been a subject of much global debate, with law enforcement and intelligence agencies saying they are finding it increasingly hard to monitor their targets online due to the proliferation of new tools such as social media, cloud computing and internet communications utilities such as Skype.

Civil liberties groups and some politicians, however, say it is a first step in a systematic erosion of privacy online. ''This extreme proposal is based on the notion that all our personal data should be stored by service providers so that every move we make can be surveilled or recalled for later data-mining,'' the Greens senator Scott Ludlam said. Also among the proposals are changes to some of the most fundamental divisions between agencies. For six decades ASIO has been the only Australian intelligence agency authorised to routinely collect intelligence on Australians. Loading However, under a proposed change, officers from Australia's foreign intelligence services, ASIS and the DSD, would be allowed to monitor Australian citizens overseas if an ASIO officer was not available.

ASIO, whose main role is to monitor people in Australia - mainly citizens - who may present a security threat, has a specific legislative framework which was created to protect people's rights. Australians monitored by ASIS or DSD would presumably not have access to similar protections.