A petition demanding an inquiry into Rupert Murdoch's dominance of Australian news media has garnered a record 420,000 signatures, overtaking a previous appeal focused on climate change.

The online petition was launched on October 12 by former Labor prime minister Kevin Rudd, a frequent target of newspapers controlled by Murdoch's News Corp.

By Friday, the call for a Royal Commission of inquiry into the impact of the group on media diversity had been signed 420,695 times on the national parliament's e-petition web page.

The petition can still be signed until November 5, when it will be submitted to parliament
The petition can still be signed until November 5, when it will be submitted to parliament AFP / William WEST

That eclipsed the previous record for an e-petition of 404,538 signatures garnered by a 2019 call for the government to declare a climate emergency.

The petition can still be signed until November 5, when it will be submitted to parliament.

Signatories included another former prime minister -- one from the other end of the political spectrum, the Liberal Malcolm Turnbull, who was ousted by hardline conservatives in a 2018 party coup supported by the Murdoch press.

An online petition launched calling for an inquiry into Rupert Murdoch's dominance over Australian media has won record public support
An online petition launched calling for an inquiry into Rupert Murdoch's dominance over Australian media has won record public support AFP / Jewel SAMAD

The Australian arm of Murdoch's New York-headquartered News Corp is the country's largest media organisation, owning papers in nearly every major city as well as cable television networks and magazines.

In launching the petition, Rudd decried the group as a "cancer on our democracy" that operated an effective "monopoly" over Australia's press.

"This power is routinely used to attack opponents in business and politics by blending editorial opinion with news reporting," the petition states.

"These facts chill free speech and undermine public debate."

Rudd, who was prime minister from 2007-2010 and briefly in 2013, has long been critical of what he says is the media organisation's "vicious" campaigning for the political right.

"There's no such thing as a level playing field anymore," he said in a video posted to Twitter.

Despite the petition's record number of signatories, its demand for a royal commission is unlikely to be acted upon by the conservative government, which generally enjoys strong support from the Murdoch press.

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