Home Secretary Priti Patel has ordered a third inquiry into the Metropolitan Police's much-criticised investigation into claims of a VIP paedophile ring.
Sparked by false claims made by Carl Beech against politicians and senior military officers, Operation Midland cost £2.5m but led to no arrests.
Beech was later jailed for 18 years for his "malicious" lies and other charges.
Now the Inspectorate of Constabulary, the police watchdog, has been told to review the force's actions.
It comes a day before the Met is due to release further sections of a separate review by ex-High Court judge Sir Richard Henriques.
Ms Patel wrote to the Chief Inspector of Constabulary, Sir Tom Winsor, on Thursday asking him to examine the police probe.
In her letter, she said: "It is imperative that the public receive assurance that the MPS has learned from the mistakes identified in Sir Richard's report and have made - and continue to make - necessary improvements.
"To this end I am writing to you to request, under the provisions in s54 of the Police Act 1996, that Her Majesty's Inspectorate of Constabulary and Fire & Rescue Services (HMICFRS) undertake an inspection at the earliest practicable opportunity to follow up on Sir Richard's review."
A report by the Independent Office of Police Conduct - expected to be published next week - previously examined the role of three detectives in applying for search warrants, but did not look into Operation Midland as a whole.
When - following Beech's convictions in July - the IOPC announced it had cleared the officers, Sir Richard criticised that outcome.
Writing about the IOPC findings in July, he said a criminal investigation should take place into what he described as the unlawful obtaining of search warrants.
Sir Richard - who conducted a review commissioned by the Met itself - stated: "I remain unable to conclude that every officer acted with due diligence and in good faith."
Harvey Proctor, who was falsely accused of murder by Beech, has also called on the home secretary to order a criminal inquiry by an independent police force.
Further chapters from Sir Richard's review on behalf of the Met are due to be made public on Friday.
However, a summary of his report published in 2016 said that 43 errors were made during Operation Midland.
These included believing the testimony of Beech - who was previously referred to as "Nick" in the media - for too long, as well as an officer referring to those claims as being "credible and true".
Sir Richard's summary added that a culture that alleged victims must be believed was a "major contributing factor" to the investigation's failing.
Met Commissioner Dame Cressida Dick, who oversaw the early stages of Operation Midland, has previously rejected demands for a new investigation into the officers involved.
Beech accused former politicians and Army and security chiefs of sadistic sexual abuse up to four decades ago.
The 51-year-old, who was described by the sentencing judge as a "manipulative and devious person", also claimed to have seen boys being murdered.
Those falsely accused by Beech, and relatives of some of those who have died since the investigation began, said the effect of his lies had been "incalculable" and they had been victims of "a totally unjustified witch-hunt".