The judge who carried out the inquiry into press standards has insisted that he had no authority to enter into the debate over the implementation of his report.
Appearing before the Commons Culture, Media and Sport Committee, Sir Brian Leveson said that as a judge he could not comment on an issue of political controversy.
MPs on the committee expressed exasperation after he repeatedly refused to say whether rival proposals put forward by the Government and the newspaper industry complied with his recommendations.
However, Sir Brian said that he could not go beyond what he had said in his report.
"I don't think I could do it because I would be entering into a political argument. I could legitimately be criticised for reaching conclusions about matters on which I had not heard evidence or listened to the contrary argument," he said.
The committee chairman John Whittingdale voiced his "frustration" over Sir Brian's refusal to comment further in the face of a political deadlock over the way forward.
"We have reached a position where the Prime Minister told me essentially we are stuck. Both sides are arguing that their version delivers your recommendations, that they will establish a system which is essentially Leveson system," he said.
"You are somebody who has spent 15 months taking evidence, you are the head of an inquiry that cost £5 million, you took evidence from a huge range of people. It would be enormously helpful if in terms of trying to resolve these differences and trying to get an agreement if we could at least get your view on that subject."
Sir Brian, however, told him: "It is all, with great respect, there. I can't unpick that further. I deliberately put it all in so that everybody could read it."
He added: "If you ask me to pick and choose then I come into the problem I'd need to know why, I'd need evidence, I'd need submissions. That's how I work, it is a judicial exercise for me and I've finished and I don't have any authority to do that."
Earlier this week, the Privy Council rejected the industry's proposals for a royal charter establishing a new system of regulation. It will meet again at the end of the month to consider possible changes to the Government's proposed charter.