Two of them are part of the School Centred Initial Teacher Training initiative, in which would-be teachers are trained wholly in schools rather than higher education institutions.

They are the Urban Learning Foundation, a consortium involving six schools in east London, and the Chiltern Training Group, based at the Challney High School for Boys and Community College in Luton.

The other two are conventional higher education teacher training institutions - Greenwich University in London and Bretton Hall College in Wakefield.

If follow-up inspections confirm the failings, the Teacher Training Agency will withdraw their accreditation and the courses would be forced to close.

'Disproportionate'

The Ofsted reports comment on just one course at each institution - English at the Urban Learning Foundation, physical education at the Chiltern Training Group and Greenwich University, and music at Bretton Hall.

Each course is judged on categories including the quality of admission procedures, the quality of training and the trainees' subject knowledge.

Greenwich University and Bretton Hall have described the Teacher Training Agency's response as "disproportionate" at a time of acute shortages of trainee teachers.

A spokeswoman for the agency said: "Prior to these four cases, 15 teacher training institutions have had to go through accreditation procedures following inspection reports. Of these, just two have had to close."