(Reuters) - Media mogul Rupert Murdoch is engaged in a legal battle against three of his children to ensure that his eldest son and chosen successor, Lachlan Murdoch, will remain in charge of his media empire, the New York Times reported on Wednesday.

Murdoch is trying to expand Lachlan Murdoch's voting power in the Murdoch Family Trust to secure a majority and ensure that he cannot be challenged by the siblings, the report said, citing a sealed court document.

The Reno, Nevada-based family trust holds the family's shares in Murdoch's vast collection of television networks and newspapers through the companies News Corp ( NWSA ) and Fox Corp. ( FOXA )

Lachlan Murdoch is chairman of News Corp ( NWSA ), whose publications include the Wall Street Journal and the Sun, and chair and chief executive of Fox Corp. ( FOXA )

The trust currently has eight votes: four controlled by Murdoch, and the remaining four controlled by the four children from his first two marriages. Murdoch's youngest daughters, Chloe and Grace, from his third wife, Wendi Deng, do not have voting rights in the trust.

In court, Murdoch is arguing that having Lachlan Murdoch run the company without interference from his more politically moderate siblings - James, Elisabeth and Prudence Murdoch - will help preserve its conservative editorial stance, thus protecting the commercial value for all his heirs, the report said.

Fox Corp ( FOXA ), News Corp ( NWSA ), and Murdoch's lawyer did not respond to Reuters requests for comment while the lawyer for the three children involved in the legal battle could not immediately be reached.

Fox News continues to be the number one U.S. cable news network, playing an influential role in U.S. politics, particularly among Republicans who prize Fox's conservative-leaning audience.

Murdoch was that worried that a "lack of consensus" among his four children "would impact the strategic direction at both companies including a potential reorientation of editorial policy and content," the report said, adding that he also wishes to hand Lachlan Murdoch "permanent" and "exclusive" control over the company, citing the court's decision.