Rupert Murdoch’s newspapers don’t do subtlety when it comes to political attacks.

Over the last week, readers of his US titles have been informed that Donald Trump is “Trumpty Dumpty”, the “biggest loser” in Republican politics, and the man who meant the “red wave” never crested in the US midterm elections.

The New York Post marked Trump’s latest bid for election with something more damning: outright mockery.

Under the headline: “Florida Man makes announcement,” the formerly pro-Trump newspaper directed readers to a story deep inside the newspaper on page 28.

“With just 720 days to go before the next election, a Florida retiree made the surprise announcement Tuesday night that he was running for president,” said the deadpan news report.

The tabloid’s print edition has a dwindling readership but the former US president is still said to be a regular reader – which means it probably hurt when they mocked his Mar-a-Lago home – raided by the FBI in August – as a “classified documents library”.

Yet while the newspaper editorials have led to suggestions that Murdoch has completed a clean break with the former US president, this misses the more positive reaction on Murdoch’s Fox News television channel.

“Murdoch has very little control over his most important outlet, which is Fox,” said Michael Wolff, the media commentator who has written three books on Trump.

“Let’s assume Murdoch was giving a message to the Post … he can’t do that at Fox. And Fox is the all-important thing.”

Although there has been criticism of Trump on Fox News in recent weeks, several presenters such as Sean Hannity and Tucker Carlson have their own loyal audiences who have been fed pro-Trump material for years. A rapid U-turn may be too much for them to take, especially if the network is accused of betrayal.

As Wolff puts it: “Each of the voices at Fox is going to be motivated by their own ratings – and if their own ratings are dependent on Trump then they’re not going to deviate. Hannity does not seem to have deviated one increment off his absolute fealty to Trump. Tucker likewise.”

In the background is Murdoch’s attempt to reunite two parts of his business empire and ultimately hand over control to his 51-year-old son, Lachlan. The family’s main media interests are separated into two businesses as a result of the News of the World phone-hacking scandal, which saw the legally troubled outlets separated.

The core business is the US-focused television business Fox, while the newspaper assets – including its UK titles – are controlled by News Corp.

Combining the two makes little business sense but would tidy up family succession planning, according to the media analyst Alice Enders: “It’s not about Rupert being back in charge, it’s about Lachlan taking over and pursuing the same traditional classic conservative agenda.”

She said that it would be hard for Fox News to find a way to let go of Trump without risking some of the hundreds of millions of dollars of advertising that flows to the network.

“Fox is the jewel in the crown. The influence that the Murdochs want to exercise is through Fox News. What’s super interesting is they want to maintain their currency as the go-to news channel for conservative voters – and they have to do that in a way that balances the Trumpistas against everyone.”

The focus on US politics also reflects a physical change in Rupert Murdoch’s location.

He has spent a substantial time in the UK in recent years alongside his now ex-wife Jerry Hall and his daughter Elisabeth.

During the Covid pandemic they were based at an Oxfordshire mansion, where he took the decision to sign up Piers Morgan for the launch of TalkTV and went to get his Covid vaccine – at the same time that his US media outlets were casting doubts on its effectiveness.

Now the recently divorced nonagenarian is increasingly based at a newly acquired ranch in rural Montana, a remote state favoured by billionaires. Official documents show that last month he paid £13,000 to fly the former prime minister Boris Johnson there for a meeting, while corporate filings suggest he is running his business empire from the ranch and has permission to hold board meetings there.

This raises the question of which Murdoch is now calling the shots: 91-year-old Rupert or Lachlan, who is managing part of the business from his family home in Australia – working late into the night on video calls due to the time difference.

The Trump years weighed heavily on Murdoch, with Fox News facing a $1.6bn lawsuit over claims it amplified Trump’s false allegations about fraud at a voting machine company after his election defeat. Murdoch’s son James has left the family business and had made barely coded criticisms of Fox News, which hit hard according to Wolff.

“In terms of Rupert himself, he has always detested Trump. Trump has been the cross to bear in his life, and the Trump effect at Fox has essentially broken up his family.”

Trump, banned from Twitter and struggling to get airtime, has not taken his ostracism lightly, whining that they were favouring Florida governor Ron DeSantis.

“NewsCorp – which is Fox, the Wall Street Journal and the no longer great New York Post – is all in for Governor Ron DeSanctimonious,” Trump said.

But as Enders puts it: “Murdoch doesn’t back losers. Trump is a loser.”