David Cameron is under intense pressure to drop his opposition to a new law backing up press reforms after he faced a backlash from victims of media intrusion.
High-profile campaigners who have suffered at the hands of the press refused to meet Culture Secretary Maria Miller because they feel "too let down" by the Prime Minister, according to pressure group Hacked Off.
Nearly 17,000 people have signed a petition launched by the organisation calling on the three main party leaders to implement Lord Justice Leveson's recommendations in full.
Divisions over how to deal with the judge's findings have also ratcheted up coalition tensions.
Liberal Democrats pledged to make sure legislation implementing the press regulation plan was drawn up "in good faith" after Tory suggestions that a Bill was only being drafted to demonstrate the proposals were unworkable.
Conservative Ms Miller insisted the "principles" of the judge's blueprint could be met without statutory backing. Asked if it was designed to prove the system would not work, and would threaten press freedom, she told the BBC: "Absolutely." Labour raised fears that officials would "gold plate" the draft legislation so it looked too complex.
A spokesman for Deputy Prime Minister Nick Clegg said: "The statement that this Bill is being drafted to show that it will not work does not reflect the position agreed by all three party leaders in the talks on Thursday And the Liberal Democrats in Government will ensure that the Bill is drafted in good faith. We owe that to the public and the victims."
Hacked Off associate director Evan Harris attended the meeting with Ms Miller and group director Brian Cathcart, and said they came away "as disappointed" as when they went in. The former Lib Dem MP said: "Maria Miller asked to meet with victims of press abuse. No victims were willing to meet with her because they felt too let down by what the Prime Minister said yesterday, and some of them frankly were too angry.
"Brian Cathcart and I met with her and conveyed our concern and frustration, and that of the victims we had spoken to about it, at the Prime Minister's position. We were left with no proper explanation of why the Prime Minister said he had an objection in principle to the core of the Leveson Report, which he had not mentioned to us previously in three meetings, and had not mentioned in his evidence to the Leveson Inquiry."
But a Tory source disputed claims that victims were due to attend the meeting, insisting that it was scheduled simply with Hacked Off organisers. The source added: "The conversation with Hacked Off was frank and open and the Culture Secretary said that she would be keen to keep an open dialogue with them as things progress."