A small Australian news website has made an unusual request to be sued by Fox News boss Lachlan Murdoch, taking on one of the world's most influential media figures.

Crikey, an often pugilistic Australian news site, published on Monday a series of legal threats it said it received from Murdoch's lawyers over commentary it published about Fox News' role in the U.S. Capitol attacks.

Murdoch is the eldest son of billionaire media tycoon Rupert Murdoch, owner of scores of outlets including Fox News, The Wall Street Journal and the New York Post.

His lawyers claimed a June article – headlined "Trump is a confirmed unhinged traitor. And Murdoch is his unindicted co-conspirator" – had defamed the media scion 22 times.

The article was mostly focused on former U.S. President Donald Trump's role in the Jan. 6, 2021, insurrection attempt.

It did not name Lachlan Murdoch specifically but it referred to the "Murdochs and their slew of poisonous Fox News commentators."

Crikey said it had decided to "fight" the threats from Murdoch's lawyers and rebuffed their demands to permanently remove the article from its website and publish an apology.

"We want to defend those allegations in court," Crikey's editor and chairperson said in a joint open letter, published Monday as an advertisement in The New York Times.

The pair framed the issue as a battle for press freedom, and said they welcomed the opportunity "to test this important issue of freedom of public interest journalism in a courtroom."

The legal tussle pits an upstart website, with subscriber numbers in the low tens of thousands, against one of the world's largest media empires.

If the case moves ahead, Crikey will have to face Australia's tough libel laws, which offer little protection to the media.

The Murdoch family remains a major player in the Australian media, despite its global expansion into the United States and Britain.

Fox Corporation declined to comment.