Ofsted is in need of an "overhaul" and is seen as "not fit for purpose" according to an inquiry chaired by former South Dorset MP Lord Knight.

The Beyond Ofsted inquiry called for "transformational change" and said it found Ofsted as "having a detrimental impact on schools which some perceive as toxic".

The inquiry, chaired by former MP Lord Jim Knight and sponsored by the National Education Union (NEU), recommends the school inspection system should be overhauled.

Lord Knight said: "The evidence is clear. Ofsted has lost the trust of the teaching profession, and increasingly of parents.

"Our recommendations are designed to restore trust and address the intensification of leader and teacher workload while reforming a system which is ineffective in its role of school improvement"

The inquiry recommends that schools could "self-evaluate their progress" and work with an external School Improvement Partner who would work long-term with the school.

They would validate and support the school to deliver an action plan and parents would be provided with readable and useful information instead of a single-word judgment.

Lord Knight added: "This would produce an action plan for governance and the school community to understand what is working well and what can be done better."

The Beyond Ofsted inquiry was launched in April amid calls for the inspectorate to revamp its school ratings system - which uses one-word judgments - following the death of headteacher Ruth Perry in January.

Ms Perry's family said she took her own life after an Ofsted report downgraded her Caversham Primary School in Reading from its highest rating to its lowest over safeguarding concerns.

Former schools minister Lord Jim Knight told BBC Radio 4's Today programme that it was "time for a radical overhaul".

Lord Knight said: "There are other ways of doing this that don't compromise on standards in any way, but are much more supportive and they're based on trust, and could actually help turn around the drain of teachers leaving the profession at the moment."

The chairman of the Beyond Ofsted inquiry, which is sponsored by the National Education Union, said the current system was "operating on a culture of fear".