David Cameron's hopes for cross-party consensus on a response to the Leveson Inquiry were dashed after Labour leader Ed Miliband insisted that a new press regulator should be established in law.
The Prime Minister said politicians should be wary of legislation which could potentially "impinge free speech and a free press".
But Mr Miliband said without a legal underpinning for any new regulator "there can't be the change we need".
Mr Cameron called for immediate cross party talks with Mr Miliband and Liberal Democrat leader Nick Clegg, the Deputy Prime Minister.
Mr Clegg sat beside Mr Cameron as he made his statement, but will use his own appearance at the despatch box to set out his views on the Leveson Inquiry in a sign of division at the top of the coalition.