Trump is reportedly worried that Fox News is being taken over by liberals trying to undermine him, as his war on the network escalates

• President Donald Trump has been complaining to friends and advisers that Fox News is not loyal enough to him, the Daily Beast reported. 
• According to the report Trump is concerned that the sons of Fox chief Rupert Murdoch, who are taking more important leadership roles in his media empire, are liberals. 
• Trump has repeatedly expressed his frustration with Fox in recent months, tweeting earlier in July "Fox News is changing fast, but they forgot the people who got them there!"
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President Donald Trump has been quizzing friends, advisers and media allies about the loyalty of Fox News, once his favorite cable network, the Daily Beast reported. 

Citing three sources who have spoken to the president about the subject recently, the outlet reported that the subject is very much on the president's mind. 

Trump has asked repeatedly "what the hell is going on at Fox?" the sources said. He is also said to have noted "I've been good to them." 

According to the report, Trump has expressed concerns that the sons of Fox owner Rupert Murdoch, who are playing key roles running their aging father's media empire, are "very liberal."

It said Trump has asked his allies at the network whether the younger Murdochs can be trusted. He has also reportedly instructed senior aides to do more interviews with networks other than Fox News, which has previously enjoyed unparalleled access to senior members of the administration.

Screenshot/Fox News

In March, Lachlan Murdoch, the eldest son of Rupert, took over as chief executive at the Fox Corporation, the parent company of Fox News, following the sale of 21st Century Fox to Disney.

According to an extensive investigation by The New York Times, he favors championing the conservative nationalist positions of hosts like Carlson. 

But his younger brother, James Murdoch, also a Fox executive, has reportedly expressed embarrassment to friends over Fox News, and takes a more liberal political position than his brother or father.

Trump's anger at Fox news may come as a surprise to many, given its frequent pro-Trump reports. Star hosts including Sean Hannity and Tucker Carlson act as informal advisers to the president. 

But the president in recent months has returned to the subject repeatedly, publicly accusing the network of bias against him.  

"Watching @FoxNews weekend anchors is worse than watching low ratings Fake News @CNN," tweeted the president in April, after the network reportedly provoked his ire by broadcasting live footage of soccer fans in a French bar chanting insults about him. 

"Fox News is changing fast, but they forgot the people who got them there!" the president wrote. 

Earlier in the year, he lashed out at the network for hosting Democratic presidential candidates in town-hall style debates.