[NEW YORK] Former 21st Century Fox chief executive James Murdoch, son of media tycoon Rupert Murdoch, has resigned from News Corp's board, according to a document released Friday by the US Securities and Exchange Commission (SEC).

A letter sent by James Murdoch to the board said the decision was due to "disagreements over certain editorial content published by the company's news outlets and certain other strategic decisions."

News Corp owns the Wall Street Journal, the New York Post, The Times and the Sun newspapers among others, but not Rupert Murdoch's Fox News network.

James Murdoch was once seen as his father's successor, but Friday's move reinforces his disengagement from the family media empire, which grew from a newspaper group in Australia.

Mr Murdoch, Rupert's younger son, headed 21st Century Fox until last year when he left after Disney acquired most of the group's assets.

James Murdoch, 47, has recently been critical of his father's business and its media coverage.

GET BT IN YOUR INBOX DAILY

Start and end each day with the latest news stories and analyses delivered straight to your inbox.

Sign UpVIEW ALL

In January, he denounced the climate change skepticism of some Murdoch media, citing coverage of the fires which devastated large parts of Australia.

He has launched his own private holding company called Lupa Systems, which among other things has taken a stake in Vice Media.

"We're grateful to James for his many years of service to the company. We wish him the very best in his future endeavors," said Rupert Murdoch, executive chairman of News Corp and James's brother Lachlan Murdoch in a statement.

AFP