The East Midlands is the “worst-performing region in the country”, where education for thousands of pupils is “distinctly second-division”, Sir Michael Wilshaw has said, after Ofsted bosses wrote to academy trusts and councils in Northamptonshire to criticise school standards.

Wilshaw said national politicians and policymakers should “worry more about what is happening north of the Wash”, claiming that Leicester’s educational ambitions and achievements did not equate to the “great sporting success” of its football team’s recent Premier League win.

The chief inspector warned that almost one in three secondary schools in the region, which had a GCSE pass rate of less than 55 per cent last year, were inadequate or required improvement, and raised particular concerns about attainment of poorer pupils and those in care.

While 46 per cent of pupils overall failed to get five GCSE A* to C grades including English and maths in 2015, this rose to 73 per cent among pupils eligible for free school meals, and more than 89 per cent of children in care.

Wilshaw’s comments were released this morning to coincide with the publication of a letter from Ofsted’s East Midlands director Chris Russell to Northamptonshire’s councils, academy trusts and schools commissioner over standards.

In Northamptonshire, where most schools are academies, almost 25 per cent of pupils attend an inadequate school or one which requires improvement, compared to 15 per cent nationally, and Russell has raised concerns that higher-ability pupils are not being supported to achieve as well as they should.

At secondary level, more than a third of the pupils attend a school that is inadequate or requires improvement, compared with 21 per cent nationally.

But Northamptonshire isn’t the only local authority area to have been singled out.

In his commentary, Wilshaw warned that Leicester was the poorest-performing council area in the country for pupil outcomes at the end of the early years foundation stage.

Performance in the key stage 1 phonics screening check in Nottingham and Derby was also criticised. Despite the fact 77 per cent of pupils nationally achieved the required standard last year, the figure in Derby was 70 per cent and in Nottingham it was 69 per cent, making it the worst-performing area in England.

Ofsted were careful to send the letter to academy trusts and the regional schools commissioner, after being criticised in April for taking Reading Council to task over poor GCSE results, despite the fact three quarters of secondary schools in the borough are academies.

Wilshaw described education for thousands of children in the east midlands as “distinctly second-division”, and warned that low standards in the region were “exposing the educational fault line dividing the nation”.

Blaming a “culture of complacency and a lack of clear accountability”, Wilshaw said the statistics highlighted should “serve as a wake-up call”.

“The poor quality of education in many parts of the east midlands often passes under the radar as attention is focused on underperformance in the bigger cities of the north and West Midlands, like Manchester, Liverpool and Birmingham.

“However, in many ways, the problems in this region symbolise more than anywhere else the growing educational divide between the south and the rest of England that I highlighted in my last annual report.”