Submitting mislaid files on historical child sex abuse at Westminster is "the test of the Home Office's transparency," according to the MP who lead the campaign for the inquiry into allegations of peadophilia at Parliament.
Simon Danczuk told Good Morning Britain failure to hand in the missing files may lead to the Home Office's permanent secretary to be recalled to answer questions from the Home Affairs select committee.
A Labour MP has launched a petition calling on the Prime Minister to "make amends for historic failures" by establishing a national inquiry into allegations of organised child sex abuse.
Tom Watson, MP for West Bromwich East in the West Midlands, said "many survivors of child abuse believe they have been let down by the system of child protection in the UK".
The petition's launch follows the Home Office's disclosure that 100 official files relating to historic abuse allegations have gone missing.
Mark Sedwill, permanent secretary to the Home Office, said the files relating to a 20-year period between 1979 and 1999 were "presumed destroyed, missing or not found".
Home Affairs committee chairman Keith Vaz described the loss of more than 100 official files relating to historic allegations of organised child abuse as being on an "industrial scale".
He told BBC Breakfast that he welcomed a letter from Mark Sedwill, the permanent secretary at the Home Office, outlining a a fresh review into the handling of the dossier.
– Home Affairs committee chairman Keith Vaz
We will want to pose further questions of course, because there's a lot of information that we didn't know was in existence that he's given us in this letter.
But also I think that the Government and Mr Sedwill should work with Parliament in fashioning a set of terms of reference that will satisfy all those who are dissatisfied with the way in which matters have been progressed so far - so I think it's an important step which we welcome.
Former Conservative cabinet minister Lord Tebbit has said he believes there "may well" have been a political cover-up over child abuse in the 1980s because "It was the thing that people did at that time."
Lord Tebbit told BBC1's The Andrew Marr Show that people's instincts during that era were to protect "the system".
Asked if he thought there had been a "big political cover-up" at the time, he said: "I think there may well have been. But it was almost unconscious. It was the thing that people did at that time."
"At that time I think most people would have thought that the establishment, the system, was to be protected and if a few things had gone wrong here and there that it was more important to protect the system than to delve too far into it," he said.
"That view, I think, was wrong then and it is spectacularly shown to be wrong because the abuses have grown," he added.
More than 100 official files relating to historic allegations of organised child abuse have gone missing, the Home Office has disclosed.
Mark Sedwill, the permanent secretary at the Home Office, said the documents - which related to a 20-year period between 1979 and 1999 - were "presumed destroyed, missing or not found".
ITV News correspondent Emily Morgan reports from Westminster:
A review into a missing dossier alleging paedophile activity in Westminster in the 1980s is insufficient by itself, the shadow home secretary said, after the Home Office revealed it would appoint a senior legal expert to carry out a fresh review. Yvette Cooper said:
Mark Sedwell is right to seek an expert from the legal profession to lead the review into how the Home Office allowed a dossier alleging paedophile activity in Westminster to go missing. If the public are to have any confidence in the findings of the investigation it needs to be thorough and independent.
However, this review alone is still not sufficient. The Home Secretary must now publish the review that was conducted in 2013.
A review into a dossier alleging paedophile activity at Westminster in the 1980s did not find a single dossier from Conservative MP Geoffrey Dickens, but several sets of correspondence over a number of years containing allegations of sexual offences, the Home Office permanent secretary has written.
In a letter to the Home Affairs committee chairman Keith Vaz, Mark Sedwill wrote: "As well as these specific allegations, later correspondence from Mr Dickens focused on broader related policy issues, such as the risk of children and young people being drawn into occult activities.
"The review found no record of specific allegations by Mr Dickens of child sex abuse by prominent public figures."
The Home Office is to appoint a senior legal figure to carry out a fresh review into how a dossier alleging paedophile activity at Westminster in the 1980s was handled by the department.
Mark Sedwill, the Home Office permanent secretary, has written to Prime Minister David Cameron to say the new investigation would assess whether conclusions of an earlier review conducted last year "remain sound".
Mr Sedwill wrote: "To provide the additional reassurance you are seeking, particularly in view of information now in the public domain since the investigation's conclusion last year, I will engage a senior independent legal figure to assess whether the review's conclusions remain sound.
"I aim to make the appointment within the next week".
David Mellor, who served under former home secretary Lord Brittan as a home office minister in the 1980s, said that a missing Westminster "paedophile dossier" was not as significant as it has been portrayed over the past week.
Speaking on his LBC radio show, Mr Mellor said he remembered "sort of chat around the department" that it "wasn't a very substantive thing at all".
"People are talking about this document as if it's a carefully worked through expose of people. There's no reason to think it was," he said.
He suggested that criticism over the way that Lord Brittan dealt with the document was becoming a "witch hunt2.
"I think it is so unfair that on the basis of what is becoming a witch hunt, he's being pilloried for handling a document... that he did pass on," he said.
Ed Miliband said there needs to be a "thorough and proper review" into the missing Westminster "paedophile dossier".
Speaking in Leeds ahead of the Tour de France, the Labour leader said that child protection experts should also "draw together all of the lessons" learnt over the last few years about child abuse.