The government has rejected growing demands for a full inquiry into the allegations of a paedophile ring having operated in Westminster in the 1980s.
Both Downing Street and deputy prime minister Nick Clegg have said they believe the police are the best people to pursue any fresh inquiries.
The development will disappoint the 130 MPs who have now backed a call from Labour's campaigning Simon Danczuk for a Hillsborough-style inquiry into historic child sex abuse claims.
They have been supported by the former director of public prosecutions, Lord Macdonald, after a dossier presented to then Tory Home Secretary Leon Brittan detailing abuse "in and around Westminster" has gone missing.
Danczuk believes the dossier, handed to Brittan by former MP Geoffrey Dickens in the mid-1980s, includes names of powerful and prominent individuals involved in a paedophile ring.
But Brittan has insisted the claims were dealt with properly at the time, with some allegations passed to the police. But no action followed and the material was not retained.
The prime minister's spokesman stressed an internal home office inquiry had been conducted last year adding: "If there are allegations or evidence then people should bring them forward to the appropriate authorities.
"We are saying very clearly that where there is wrong-doing it is absolutely right it should be the police who look into these matters."
Meanwhile deputy prime minister Nick Clegg said he would support anything that helped get to the truth.
"My view is, given the very serious criminal nature of these allegations, namely that there was a circle of people who hid what they were doing . . . abusing vulnerable children in children's homes, the only way to deliver justice, even in the years afterwards, is allow the police to get to the bottom of these things."
But the former DPP, Lord Macdonald said the issue was "alarming" and called for an investigation into the dossier: "what happened to it and indeed what the police did when they received it".
Meanwhile Barry Dickens, whose MP father Geoffrey died in 1995, told ITV News that shortly after his father passed the documents to Lord Brittan, the family home was burgled twice but that nothing was taken on either occasion.
Danczuk told a Commons committee this week that he believed politics was "the last refuge of child sex abuse deniers" and later added that refusal to hold an inquiry would fuel the claims of a conspiracy to cover up names.