David Cameron is "stepping back" from implementing the Leveson Report's recommendations in full, a victim of press intrusion has claimed.
Christopher Jefferies said he was very happy with the report produced by Sir Brian Leveson, but it was "unfortunate" that the process after its publication had been so "tortuous".
He also stressed that it was important the second stage of the Leveson Inquiry, looking at phone hacking, took place.
Giving evidence to a Lords select committee examining the Inquiries Act, Mr Jefferies said implementation of the recommendations of a public inquiry was "key".
Mr Jefferies, who was wrongly arrested over the 2010 murder of Joanna Yeates in Bristol, told the peers: "As far as my experience of the inquiry and its outcome are concerned, in terms of the report of Lord Justice Leveson, I'm very happy indeed."
But he added: "It has been rather unfortunate that we have had such a tortuous procedure to get to where we have with the, I hope, imminent sealing of the cross-party charter at the end of this month."
A royal charter agreed by the three main political parties is due to be approved by the Privy Council later this month, setting up a panel which could approve a new regulator.
But, without naming the Prime Minister, Mr Jefferies criticised politicians for rowing back from the regulatory regime proposed by Sir Brian.
Mr Cameron had previously said he would implement the judge's recommendations unless they were "bonkers".
Mr Jefferies told peers: "It was rather unfortunate in that, having in effect set up both before and during the inquiry his own tests as to whether or not the recommendations would be acceptable - namely that the Leveson recommendations had to be acceptable to victims as well as the press and politicians and that they would be implemented unless they were bonkers - there was a considerable stepping back from what everybody had taken to be that commitment once the report of the inquiry was published."
Giving evidence to the same Lords committee earlier this month, Sir Brian hinted that the planned second part of his inquiry, dealing with phone hacking, may never happen.
He said: ''I hesitate to say it, there is within the terms of reference another part of this inquiry.
''I don't know when anyone will consider that. Certainly not at the moment. But that is not for me to say.''
But Mr Jefferies said: "I would like to emphasise the importance, in due course, of part two of the inquiry taking place."