The current rules are designed to stop a person controlling television, radio, and print media in the same town, known as the two-out-of-three rule. But the rules were written in the early 1990s and only apply to newspapers that are printed four days a week.

In theory, newspaper owners would be free to buy another licence if they only print papers on the weekend, according to acting chair of the Australian Communications and Media Authority, Richard Bean.

"If [Fairfax] stop publishing Monday to Friday, or Monday to Thursday, then The Age and the Sydney Morning Herald will no longer count for those ownership and control laws," Mr Bean said.

"Fairfax can't buy a television station and a radio station and publish a daily newspaper in the same market. But if you stop publishing daily – and Monday to Friday is online – you can."

Chief executive of Fairfax Media Greg Hywood told investors in 2016 that 65 per cent of advertising revenue comes from weekend papers.

"It should surprise no one, and certainly not us, that the seven-day-a-week publishing model will eventually give way to weekend-only or more targeted printing for most publishers," he said at the Macquarie investor conference.

However, this week a Fairfax spokesman said there were "no plans to change from daily printing and we expect that to be the case for some years into the future."

The investment community expects Fairfax Media to "formally outline its plans for a move to a digital-only weekday model for the metro titles", according to a note by media analyst Fraser McLeish at Credit Suisse.

He estimates weekend-only printing would cost Fairfax Media about $77 million in lower circulation, but could save about $117 million in costs.

According to the Broadcasting Services Act 1992 a newspaper is one "in the English language and is published on at least four days in each week".

Bizarrely, national newspapers like Fairfax's The Australian Financial Review and News Corp's The Australian are not counted as newspapers because the cross-media rules only focus on "newspapers associated with the licence area of the [radio] licence".

Each broadcast licence area is based on Census boundaries. The population within each licence area ranges from a few hundred in remote areas to more than three million people in Sydney.

"There are, in fact, no national broadcasting licences. They are all regional. It is just that people think of them as national because they are national networks. But the broadcasting licences are a geographical thing," Mr Bean explained.

"It wouldn't matter what [Fairfax] do with The Canberra Times, as far as ownership of media assets in Sydney were concerned," he added.

New media ownership laws proposed by the Turnbull government in late 2016 would scrap the two-out-of-three ownership rules in favour of limiting the number of radio or television licences a person can control.

"The digital age is now defined by the wide range of media voices and perspectives available to consumers," the Department of Communications' website states. "In this environment, protections such as the '2 out of 3 rule' are no longer needed but some protections will still remain."

Labor has said it would pass most of the government's package, but wants to keep the two-out-of-three rule to prevent further ownership consolidation and because not all Australians have reliable access to online news.

"The current laws ... are directed at the traditional media, and evidence about the efficacy of the two-out-of-three rule, with regard to the future of the print editions of the weekday papers, was before the Senate Inquiry when it considered the Broadcasting Legislation Amendment (Media Reform Bill) 2016 last year," a spokesman for Labor's acting communications spokesman, Mark Dreyfus said.

Fairfax Media currently has a 54.5 per cent stake in Macquarie Media Limited, which owns commercial radio licences in Melbourne, Sydney, Brisbane and Perth. It does not have any television licences, but is in a joint venture with the Nine Network to operate Stan, a subscription video-on-demand service.

News Corp does not directly own any commercial broadcast television or radio licences.

However, News Corp co-chair Lachlan Murdoch has a 7.7 per cent stake in Channel Ten and Foxtel, which News Corp owns half of, also owns a 13.8 per cent stake in Ten. (Subscription television service Foxtel is not included in media ownership laws).

Mr Murdoch also fully owns Nova Entertainment, which runs Nova and Smooth FM and Fiveaa stations.