The Metropolitan Police waited three years before acting on a damning review of the investigation into false claims of a VIP Westminster paedophile ring made by former Swindon hospital worker Carl Beech.

Her Majesty’s Inspectorate of Constabulary and Fire and Rescue Services found force chiefs were concerned with restricting access to the 2016 report by former High Court judge Sir Richard Henriques, which identified 43 police failings.

A detective described the fallout of the botched Operation Midland investigation as “one of the most secret learning experiences the Met has had.”

The watchdog made 16 recommendations, which include proposals that may change the way police approach victims in investigations.

Former Tory MP Harvey Proctor described the report as a devastating criticism of the Met.

Operation Midland was launched in 2014 to investigate allegations of rape, torture and murder by well-known names from the military, security services and politics made by fantasist Carl Beech, then known as “Nick”. It ended without a single arrest.

The 16-month probe saw dawn raids on the homes of D-day veteran Lord Bramall, the late Lord Brittan and Mr Proctor following Beech's claims. He is now serving an 18-year jail term for perverting the course of justice.

HMICFRS report found the Met had not done enough to learn lessons in 2016 and had only started acting on some of the recommendations towards the end of last year.

Mr Proctor said: “It looks as though the Met Police did nothing, or at least very little, between receiving the Henriques report and the Home Secretary asking the inspectorate to look at what the Met Police had done.

“It looks as though the Met only started to do things once they knew the inspectorate had been commissioned by the Home Secretary to report on it. They were not learning the lessons of the Henriques report and there is evidence in this report that instead of taking into account what Henriques said and putting into place the recommendations in that report, the Met were doing their level best to make sure the full Henriques report never saw the light of day.”

The HMICFRS review found an advisory group set up in the wake of the Henriques report had no formal plan to implement the recommendations, leading to an “underwhelming approach” to learning lessons during 2017, 2018 and 2019. A senior detective told inspectors the Henriques report was “one of the most secret learning experiences the Met has had”.

HM Inspector of Constabulary Matt Parr said: “We were pretty underwhelmed by the Met’s response for the first three years. It’s pretty clear generally learning lessons from the Henriques report doesn’t seem to have been the top priority and it should’ve been.

The Met said it had been deliberately cautious due to criminal proceedings and an IOPC investigation.