James Murdoch has dramatically quit as director of the companies that publish the Sun, The Times and the Sunday Times

James Murdoch has dramatically quit as director of the companies that publish the Sun, The Times and the Sunday Times and analysts said he could soon sever all ties with the troubled newspaper group.

The surprise move, which has seen Rupert Murdoch's son resign a string of directorships at News International, also raises questions about parent company News Corporation's commitment to its newspapers.

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. NI insisted that James Murdoch was not walking away from the UK newspaper arm.

A spokesman said: "James Murdoch doesn't step back from NI. He remains chairman." He is also still 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.