David Cameron has come under fresh pressure to push ahead with a new system of press regulation as he prepares to be grilled by senior MPs about the response to the Leveson Inquiry.
Victims of press intrusion have written an open letter to the Prime Minister ahead of his appearance before the Liaison Committee calling on him to reject a proposed scheme put forward by the newspaper industry.
Instead the signatories, including Kate and Gerry McCann - whose three-year-old daughter Madeleine went missing in Portugal six years ago - and Harry Potter author JK Rowling, urged the Prime Minister to make progress on the Royal Charter plan which received cross-party backing in March.
The charter had been due to be presented to the Queen for approval on May 15 but it was put back to give more time for consideration of the alternative charter put forward by the industry.
In July, Mr Cameron said he believed the alternative charter put forward by the press had "some serious shortcomings" and he still supported the document backed by the Commons.
The letter to Mr Cameron, organised by campaign group Hacked Off, claims that the alternative proposal, which would avoid any state underpinning for the new regulatory regime, "clearly lacks the key elements of independence and effectiveness" that Lord Justice Leveson recommended in his report on press standards.
The signatories told the Prime Minister to "do all you can to expedite" the original charter process "so that the process of implementing the Leveson recommendations may begin".
The letter said: "We are dismayed by the attitude of the leaders of much of the press industry. They have shown no real regret for the grave failures identified in the report of the Leveson Inquiry, nor have they engaged in sincere dialogue with the public, with Parliament or with us about implementing the careful recommendations made by Lord Justice Leveson to remedy these failures.
"Instead they have consulted each other and unsurprisingly reached agreement on so-called solutions that are in their interest rather than the public's. They have engaged in a cynical manoeuvre to delay the approval of Parliament's Royal Charter, by submitting an alternative non-Leveson-compliant Royal Charter of their own.
"Several papers continue to abuse the power of the press in the attempt to discredit the Leveson Inquiry and those who challenge them, and to seek to bend politicians to their will."