Downing Street has insisted the agreement reached on Leveson is "not in any way" a statutory underpinning of press regulation - but was unable to confirm whether David Cameron was awake as the deal was done in the early hours of Monday morning.
"There is no press law, there is no statutory underpinning of press regulation," the prime minister's official spokesman said on Monday morning. "It is not in any way the underpinning of press regulation in statute."
"What you have today, which is a good thing, is cross-party agreement on a royal charter approach that the prime minister proposed several weeks back."
The prime minister blew up the cross-party talks on reaching a deal on press regulation on Friday and was preparing for a showdown vote in the Commons today.
However, over the weekend, the parties went back to the negotiating table after it appeared the Conservative Party was heading for a defeat at the hands of a Lib Dem-Labour alliance.
Ed Miliband and Nick Clegg had argued for the statutory underpinning of newspaper regulation, as recommended by Lord Justice Leveson - a course rejected by Cameron who said he feared it would endager the freedom of the press.
Labour and the Tories are embroiled in a war of words over who had emerged on top from the fraught, late-night negotiations and today's compromise deal.
In a sign of the confusion in Westminster, Downing Street described the approach as having "enshrined a non-legislative approach".
On Monday morning, Cameron said the outcome of the talks was that "everyone has accepted my argument for a royal charter".
"What we wanted to avoid and what we have avoided is a press law. Nowhere would it say what this body is, what it does, what it can’t do, what the press can or can’t do – that, quite rightly, is being kept out of parliament," he said.
"So no statutory underpinning, but a safeguard that says politicians can’t in future fiddle with this arrangement."
However, an Opposition source told the Press Association the Conservatives were simply trying to save face, insisting: "This is not a little bit of statute, this is not a dab of statute, this is statute pure and simple."
The deal was struck between Ed Miliband, Nick Clegg and Conservative Cabinet Office minister Oliver Letwin, as well as representatives of pro-Leveson Report group Hacked Off, in the Labour leader's office in the early hours of Monday morning.
The prime minister's spokesperson said Cameron was "kept in close touch" as the negotiations progressed, but was unable to confirm whether or not he was awake as Letwin led for the Tories against the Lib-Lab alliance.
But Conservative sources told The Guardian it was "completely incorrect" to say that Cameron was asleep when the negotiations were being concluded.
Culture secretary Maria Miller, who was also not present during the late night talks, insisted this morning it was "absolutely clear there is no statutory underpinning for the approach we are taking".
She said a clause being inserted into the Enterprise and Regulatory Reform Bill would "simply reiterate the fact that there can be no change to the charter as we move forward".
The parliamentary suggested amendment clause does not explicitly refer to the royal charter related to the press but rather all royal charters.
It states: "Where a body is established by Royal Charter after 1 March 2013 with functions relating to the carrying on of an industry, no recommendation may be made to Her Majesty in Council to amend the body's Charter or dissolve the body unless any requirements included in the Charter on the date it is granted for Parliament to approve the amendment or dissolution have been met."
Nick Clegg said the cross-party talks had been "painstaking" and he had been working "flat out" to get agreement before a potentially divisive Commons vote due this evening.
"It is always best when these controversial things are settled by consensus," he said.
"I think we have struck the right balance by protecting the freedom of the press and making sure that innocent people cannot be unjustifiably harassed and bullied by powerful people in the press."
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