Ofsted and the Care Quality Commission (CQC) were so concerned about the failure of Surrey County Council to tackle rising absence rates that they have taken the unusual step of asking the Department for Education and NHS England to step in to consider the next steps.
A report, which followed an inspection of Surrey by Ofsted and the CQC in March, showed the proportion of mainstream pupils with an education, health and care plan missing more than 10 per cent of school time had risen from 20.1 per cent to 21.5 per cent over a two-year period.
"The local area has advanced plans in place to extend relevant specialist provision and support across the local area.
"Plans include the implementation of some aspects urgently, through interim measures. However, in the meantime, serious issues affecting the attendance of pupils with SEND remain unresolved," the report said.
Ofsted and the CQC said the lack of sufficient progress against all of the weaknesses identified in the written statement Surrey was asked to draw up following the 2016 inspection, but in particular the lack of progress in reducing absence rates, meant the case would now be handed over to the DfE and NHS England.
"It is for the DfE and NHS England to decide the next steps. This may include the Secretary of State using his powers of intervention.
"Ofsted and the CQC will not carry out any further revisits unless directed to do so by the Secretary of State," it said.
Inspectors asked the council's service leaders and the area's health providers to submit a written statement of action in 2016 after identifying "significant areas of weakness" in the provision of SEND services.
Among these were a significant backlog of cases, the difficulties faced by parents in getting a timely and accurate assessment of their child's needs and a subsequent lack of confidence in the local area's leaders and services.
Children and young people across the county were experiencing "unequal health and therapeutic provision" and a planned move to a single, county-wide community health provider from 2017 had not yet been established.
The report highlights the increasing absence and exclusion rates for children and young people with SEND had "not been recognised by the local area as a priority for action".
It said rates for pupils with SEND had increased after a previous reduction and absences for Surrey pupils at school support were above the national average for this group in 2015.
"There is a lack of clarity in the local area about the role of GPs in identifying a child or young person as being unfit for school due to anxiety linked to autism.
"As a result, some pupils experience unnecessary unauthorised absences and have limited support for learning at home. This issue is one of considerable importance to parents," the report said.
The findings from the latest inspection also highlighted parents' unwillingness to accept a school placement they considered inappropriate.
School leaders reported there was insufficient local area capacity to meet pupils' SEND through "timely appropriate support or specialist provision".
Julie Iles, Surrey County Council cabinet member for all-age learning, said the report recognised progress that had been made in the timeliness and quality of assessments and plans.
Progress had also been made in the involvement of children, parents and carers in the planning and evaluation of services as well as the early identification of SEN by schools.
But she said more needed to be done to uncover the causes of higher rates of absence among young people with SEND.
"We know we need to do more and are absolutely committed, along with our partners, to making sure support for children is the very best it can be.
"We're working with families and health and education partners on transforming our SEND services and the strengths highlighted in this report lay crucial foundations for that work," she said.
Earlier this year Surrey won a high court challenge brought by a group of parents over £21m of potential cuts to SEND funding.
The case, which was brought after claims the proposals were made without consultation, was dismissed as no actual decision had been made by the council.