David Cameron has again rejected Labour demands for an inquiry into his Culture Secretary Jeremy Hunt's links with Rupert Murdoch's News Corporation.
Mr Cameron had to cancel a local election campaign visit and a planned speech after Commons Speaker John Bercow granted Labour leader Ed Miliband an urgent question to the Prime Minister in the House of Commons.
Mr Miliband told MPs that Mr Cameron was "defending the indefensible", after the exposure by the Leveson Inquiry of emails which showed that a News Corp lobbyist was passed advance information about a sensitive parliamentary statement by Mr Hunt's special adviser Adam Smith.
Mr Smith quit, admitting he "went too far" in his contacts with Fred Michel, but Mr Cameron made clear that he remains determined to hang on to his Culture Secretary, who sat beside him on the Government front bench.
He said he believed Mr Hunt "acted fairly and impartially and in line with the advice of his permanent secretary", adding: "I have seen no evidence to suggest that, in handling this issue, the Secretary of State acted at any stage in a way that was contrary to the ministerial code."
He accused Labour of playing "one-sided party politics" with the issue, and repeated his denial that he had made a "grand bargain" with News Corp to allow it to take control of BSkyB in return for the support of its newspapers - something he said he would deny on oath if required to before Lord Justice Leveson.
But Mr Miliband claimed Mr Hunt had breached three clauses of the code and repeated Labour's demand for Mr Cameron to refer the issue to his independent adviser on ministerial conduct Sir Alex Allan. He said: "The Prime Minister is defending the indefensible and he knows it.
"The special adviser had to go to protect the Culture Secretary. The Culture Secretary has to stay to protect the Prime Minister. The Prime Minister has shown today he is incapable of doing his duty: too close to a powerful few, out of touch with everyone else."
Meanwhile, a new poll suggested nearly half of the population believes Mr Hunt should resign. Research found 16% of voters think the Secretary of State should remain in post while 49% want him to quit over his links with Rupert Murdoch's News Corporation.
The ComRes poll for ITV News at Ten also found three out of five voters want an independent probe into whether Mr Hunt was involved in the passing of information to News Corp during its bid for BSkyB.