Noel-Baker school was recently rated inadequate in every category with inspectors blaming “messy” talks over academy status having a “negative impact on vital school improvement work”.

The school, which is maintained by the local authority,  was built as part of a £64 million Building Schools for the Future refurbishment paid for under Private Finance Initiative (PFI) funding.

Issues over its costs slowed down the school’s conversion to join the established LEAD Academy Trust.

Previous reports have revealed how other PFI funded schools were denied transformative takeovers because trusts did not want to take on their often onerous PFI liabilities.

Sceptics point out that the Ofsted criticism further questions the government’s claim that academisation is a method to deliver rapid improvement. Last week another school left in limbo as academy sponsorship talks drag on was also rated inadequate.

Baverstock academy, in Birmingham, faced closure before a volte-face from former regional schools commissioner Pank Patel. The school was awaiting an update in October – but is still in the dark.

Malcolm Trobe the interim general secretary at the Association of School and College Leaders, said schools that required “rapid and accelerated” intervention were being left stranded saying:

“These complexities have made the school situation worse.”

Inspectors reported that leadership and management at Noel-Baker was “inadequate in many respects”.

Safeguarding was ineffective, with outcomes for pupils “unacceptably low for far too long and showing little sign of improving”. The school consulted on academy changes last year and had hoped to convert by September this year.

However, academy sponsorship negotiations have dragged on. A spokesperson for LEAD told Schools Week this was because of “complexities and affordability issues” surrounding the school’s PFI agreement.

“The trust has done everything it can to support an efficient conversion process. However, some issues have been beyond the trust’s control.”

But they said the schools would join the trust in January.

In an academy conversion document published on its website, Noel-Baker said:

“Additional monies have been sourced from the DfE to support any extra costs – this is normal for PFI-funded schools.”

However, the trust said it had not received any additional monies  from Noel-Baker.