Mr Abbott later confirmed internet service providers were only being asked to store metadata, likening the information to that included on the ''front of an envelope'', but not the contents of the letter.

Senator Brandis later appeared to contradict Mr Abbott when, in an interview on Sky News, he said that all that would be captured under the government's proposed changes was ''the electronic address of the website''.

''What you are viewing on the internet is not what we are interested in … what the security agencies want to know, to be retained, is the electronic address of the website,'' he said.

The primary focus of the new laws was combating terrorism, Senator Brandis said, ''but the fact is that access to metadata is an extremely useful investigative tool. I understand, for example, that when Jill Meagher was murdered in Victoria a little while ago it was access to metadata that assisted the Victorian police in tracking down her killer.''

Internet service providers have warned of additional costs - or a so-called surveillance tax - under the push for uniform data retention laws that could see them pass the costs on to consumers.