A Kent secondary school has been kept waiting a staggering six years to become an academy because of a protracted bureaucratic wrangle, it has emerged.

And another has been prevented from converting to an academy four years after it sought a change in status. The delays are thought to be the longest on record for any conversion to an academy in the country.

The two schools are Ashford’s North School and the Royal Harbour Academy, formerly the Ellington and Hereson School, in Ramsgate.

Both schools are in limbo because of a complicated and long-running wrangle over multi-million pound private finance deals that were agreed by the county council before the schools sought a change in their status.

In the case of the former Ellington and Hereson school, now known as the Royal Harbour Academy, it is now six years since it sought government approval for it to convert to an academy and join the Coastal Academies Trust.

The extraordinary delays are being attributed to a financial dispute over who should be liable for repaying the costs associated with rebuilding and development of the two schools under the Private Finance Initiative (PFI).

Banks who put up the money for redeveloping the two schools are demanding assurances that were there to be any risk to repayments, the county council should be liable. KCC says that the risks of any default are minimal.

While the day-to-day running of the schools in question is broadly unaffected, the failure to get confirmation of their conversions has been criticised.

Paul Luxmoore, the executive headteacher of the Coastal Academies Trust, said the school was being prevented from using its powers to innovate under the academy programme and raised difficulties when it came to accountability.

“It does matter because this is a school which has one of the more challenging and vulnerable pupils of not just Kent but the whole of the south east. We find it very hard to understand why KCC has an issue with the finances because in every other part of the country, there is no issue with PFI deals.”

“For any other multi-academy trust, the legal responsibility for their schools is very clear and very real. However, for the most challenging school in the south east, responsibility is completely muddled.”

John Whitcombe, who leads the Swale Academies Trust, said the delay had caused uncertainty and was limiting the school.

“The school is a good school but keeping it good over the long term can only be done with stability and key lines of responsibility. To be fair to the county council it has given us a contract but I do hope that we can settle this soon and move on.”

KCC said it was working hard to resolve the dispute.

Cllr Roger Gough, cabinet member for schools, said:“Whilst the work done to date has resolved most of the PFI-related issues, a new issue, relating to factors they feel may jeopardise them continuing to receive contractual payments from Kent, has recently been raised by the PFI provider’s lenders.

"KCC is working closely with the RSC (Regional Schools Commissioner) and ESFA (Education and Skills Funding Agency) to try to resolve this issue. KCC, the schools, We would all like to conclude the conversions as soon as possible but must balance this against the risk to taxpayers.”

A statement from the Department for Education said: “Between April 2016 and March 2017, the average time for schools rated ‘inadequate’ to convert was 8.5 months but we recognise there is more to do to speed the process up. That’s why we have developed a range of approaches to address barriers and are investigating what more can be done to improve conversion times.”