LONDON: British politicians, struggling in their bid to find out who knew what about phone hacking at a Rupert Murdoch tabloid, have recalled son James for further questioning after employees contradicted his repeated claims of innocence.

James Murdoch, chairman of News Corp's British newspaper arm, spent almost three, uncomfortable hours in front of a parliamentary committee with his father in July, answering questions over what they had done to unravel the scandal at the News of the World.

But James's testimony, and his insistence that he did not know the problem stretched beyond 'one rogue reporter' until earlier this year, has since been undermined by two senior employees who say they made him aware of a wider problem in 2008.

John Whittingdale, the head of the Culture, Media and Sport committee, told Sky News it would recall James Murdoch to appear for further questioning. He said it expected him to appear.

He also said he would have further questions for Les Hinton, the most senior News Corp executive to stand down over the scandal.