Culture Secretary Maria Miller has said she expected the industry to come up with a process and timetable today.
Officials at Mrs Miller's Culture Department are drawing up a draft Bill to enact the Leveson recommendations in full.
But she has indicated that she expects it to confirm concerns about the complexity and potential negative impact on press freedom.
Deputy Prime Minister Nick Clegg, who is opposed to Mr Cameron's stance, said he hoped "gridlock" could be avoided in the continuing cross-party talks.
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