A former Tory MP has accused Scotland Yard chiefs of allowing a 'cover-up' of misconduct surrounding the force's disgraced VIP child abuse inquiry.

Harvey Proctor delivered his stinging rebuke after a top officer rejected his criminal allegations against detectives in the case.

Mr Proctor was falsely accused of being a serial child killer by the fantasist previously known as 'Nick' – whose claims the Met once described as 'credible and true'.

Mr Proctor spoke out after Assistant Commissioner Helen Ball's decision to deny his demands for a new, independent investigation into the conduct of five key officers.

Former Tory MP Harvey Proctor has accused Scotland Yard chiefs of allowing a 'cover-up' of misconduct surrounding the force's disgraced VIP child abuse inquiry

He said the force's attitude could best be described as 'a failed authority marking its own homework' and accused senior officers engulfed in the scandal of being part of a 'self-preservation society'.

Miss Ball is a key ally of Scotland Yard Commissioner Dame Cressida Dick, who sanctioned the launch of the disastrous inquiry and is separately under investigation for alleged misconduct in the case.

Mr Proctor revealed he has appealed against Miss Ball's decision and called on the police watchdog to review its previous decision to clear five other officers of wrongdoing.

He said: 'I await with interest to see if the Independent Office for Police Conduct again allows the police to get away with it and continues to participate in the cover-up. Even at this late stage the IOPC can institute a thorough and rigorous inquiry.'

His statement piled pressure on ex-Metropolitan Police deputy assistant commissioner Steve Rodhouse, who oversaw the running of the inquiry, codenamed Operation Midland – and was later promoted to become the £245,000-a-year head of operations at the National Crime Agency.

In November Mr Proctor announced he had reported five former Scotland Yard officers – including Mr Rodhouse – for alleged criminality during Operation Midland.

Citing 'fresh and new evidence' of wrongdoing, he revealed he had made allegations of perverting the course of justice and misconduct to an independent force, Northumbria Police, which passed them to the Met.

Scotland Yard Commissioner Dame Cressida Dick (right) sanctioned the launch of the disastrous inquiry and is separately under investigation for alleged misconduct in the case. The Yard's witness known as Nick was in fact former nurse Carl Beech, 51, (left) who was jailed for 18 years last July for his lies about VIP child abuse

Mr Proctor, 72, lost his 'home, job and repute' when officers raided his house as part of Operation Midland.

Yet, despite the force paying £100,000 in compensation to both former Armed Forces chief Lord Bramall and the widow of Lord Brittan – and more recently £500,000 to Mr Proctor – not one officer has faced any punishment.

Last year a former High Court judge, Sir Richard Henriques, savaged police watchdogs who cleared five 'Nick' scandal detectives. He said justice had been 'perverted'.

In a separate move ex-senior district judge Howard Riddle said in October he was 'misled' by Operation Midland officers seeking permission to raid the homes of Mr Proctor, Lord Bramall and Lord Brittan, all falsely accused of appalling child sex crimes.

The Yard's witness known as Nick was in fact former nurse Carl Beech, 51, who was jailed for 18 years last July for his lies about VIP child abuse.

In a letter this month to Miss Ball, head of professionalism at Scotland Yard, Mr Proctor said: 'You have decided, on flimsy pretext, that my complaints are not worthy of formally recording and therefore not to investigate them.' He said her view was not supported by Sir Richard or Mr Riddle.

Mr Proctor, who made the letter public yesterday, said: 'This is not the end of the matter.' He warned Miss Ball's actions and those of the Met would be considered by MPs and a public inquiry.

Miss Ball said in letters to him that seven of his eight allegations had already been investigated or were 'out of time', adding that he had already been apologised to.