Mr Cameron's office received six advance copies of the "hefty" report on Wednesday and was due to convene a coalition meeting on Thursday morning to try to thrash out a joint response with his Liberal Democrat Deputy Prime Minister, Nick Clegg.

But Mr Clegg also approached the Speaker of the House of Commons to ask that he be permitted to make a statement separate to Mr Cameron's.

Politicians of all parties are divided over whether freedom of the press should prevail over the need to constrain the worst excesses of Britain's rabid tabloids, such as the phone-hacking scandal that led to the Leveson inquiry 16 months ago. The public overwhelmingly wants laws to keep papers in line, with a poll on Tuesday reporting that 79 per cent wanted an independent press regulator established by law.

Only 9 per cent supported the idea of newspapers setting up their own body to deal with complaints and decide sanctions if journalists broke agreed codes of conduct.

The associate director of the lobby group Hacked Off, Evan Harris, said of the poll: "The results hardly vary whether voters read The Guardian or The Daily Mail, and are held as strongly by Conservative swing voters as by Labour voters."

But that same day, 86 MPs, including 76 Tories, wrote to The Guardian opposing statutory regulation, warning that "state licensing is inimical to any idea of press freedom". That contrasted with a letter earlier this month from 44 different Conservative MPs, who demanded statutory regulation.

Mr Cameron was believed to be considering a free vote in Parliament, given the widely differing views.

The actor and phone-hacking target Hugh Grant said victims did not want statutory regulation but independent regulation "underpinned by statute, which is a very different beast".

"What people are campaigning for is an end to newspapers being able to regulate themselves, marking their own homework," Grant said.

The London mayor, Boris Johnson, said any kind of state regulation was "preposterous".

"The British media is one of the glories of our country. They keep politicians' feet very firmly held to the fire, which is absolutely right," he said.

Tom Mockridge, the chief executive of News International, the Murdoch-owned company whose paper News of the World was killed off as a result of its phone-hacking, said he backed tougher press regulation but warned the government not to "cross the Rubicon".

"The people who argue for state regulation are saying they are going to trust the politicians in this country for another 300 years not to exploit that. That's a trust too far," Mr Mockridge said.

Lord Justice Brian Leveson was asked to look at the ethics, culture and practices of the press, and its relationships with the public, police and politicians. This followed newspaper revelations of widespread phone-hacking, including the hacking of the voicemail of a murdered schoolgirl, Milly Dowler, and questions as to why police repeatedly failed to investigate the practice.

The 184 witnesses included the former culture secretary Jeremy Hunt, Rupert Murdoch and his son James, and the former News International executive Rebekah Brooks.

with Guardian News & Media