James Murdoch has dramatically resigned as a director of the companies that publish The Times, The Sunday Times and The Sun.
The surprise move, which has seen Rupert Murdoch's son quit a string of directorships at News International, raises questions about parent company News Corporation's commitment to the troubled UK newspaper group.
Companies House filings show James Murdoch has stepped down from the boards of both News Group Newspapers Limited, publisher of The Sun, and Times Newspapers Limited, which operates The Times and Sunday Times.
NGN used to operate the News of the World and remains embroiled in legal action over phone-hacking.
The departures come as James Murdoch also faces calls to quit as chairman of BSkyB at next week's annual general meeting. His decision means no member of the Murdoch family now sits on the boards of the flagship UK papers.Rupert Murdoch used to be a director of NGN and TNL but stepped down after his son took over as NI executive chairman in 2007. James Murdoch has also quit at least one other subsidiary, News International Holdings.
Tom Mockridge, former boss of Sky Italia who replaced Rebekah Brooks as NI chief executive in July, has taken over from him at NGN and TNL.
NI insisted that James, who was promoted to News Corp deputy chief operating officer in New York in April, was not walking away from the UK newspaper arm. A spokesman said: "James Murdoch doesn't step back from NI. He remains chairman."
He also continues as a director of key holding company NI Group Limited and of Times Newspapers Holdings, the editorial board set up in 1981 to ensure the independence of the paper when Rupert Murdoch bought it.
However, those close to Murdoch say he now has a more hands-off role.
Claire Enders, founder of Enders Analysis, said: "Because it is inescapable that there will be some kind of censure from the Culture, Media and Sport select committee, it is inevitable that people will say maybe you've got too much on your plate, it makes sense to step back from some of the roles." But Enders said Murdoch still faces intense pressure as the police investigate hacking at the News of the World.
"He can step down from all these positions but he won't stop any of the other issues surrounding his stewardship," she said.
Enders dismissed talk News Corp would sell the UK papers.