''THE case has yet to be made'' for a controversial plan to force internet providers to store the web history of all Australians for up to two years, according to Attorney-General Nicola Roxon, who has acknowledged the financial and privacy costs of such a scheme.

Ms Roxon expressed her reservations in an interview with Fairfax Media, publisher of this article, in what may be a sign the government does not have the appetite for forcing through Parliament the most controversial proposal among a package of more than 40 national security measures.

Nicola Roxon. Credit:Andrew Sheargold

The proposals, if passed, would be the most significant expansion of the Australian national security community's powers since the Howard-era reforms of the early 2000s.

Regarding data retention, Ms Roxon said she had some sympathy for the view of the national security community but said: ''I am not yet convinced that the cost and the return - the cost both to industry and the [civil liberties] cost to individuals - that we've made the case for what it is that people use in a way that benefits our national security. I think there is a genuine question to be tested, which is why it's such a big part of the proposal.''