Potential teachers are turning their backs on the profession because of the refusal by Coalition ministers to make decisions about funding training courses for this September, university tutors have warned.
Next year's PGCE and undergraduate degree courses start in just seven months, but teacher trainers still have no idea how many students they can accept.
Each university is allocated a quota of students, with numbers usually announced the previous September. But Department for Education officials have yet to give them the information for next year.
Applicants are so concerned, say universities, that they are abandoning plans to train as teachers and pursuing other career paths.
James Noble Rogers, executive director of the Universities' Council for the Education of Teachers, has written to education secretary Michael Gove to tell him "many applicants are withdrawing and seeking alternative career options".
"There are significant numbers of potential teachers abandoning plans to do a teacher training course at most universities," Mr Noble Rogers told The TES.
Anne Edwards, director of Oxford University's department of education, said: "This situation is very difficult. We are offering conditional places to students, but we hope they don't find this too unstable."
Andy Jones, dean of the Institute of Education at Manchester Metropolitan University, said: "We've never had to wait as long as this for allocations. It is making life extremely difficult for everyone.
"We can't plan our school placements for trainees because we don't know how many people will need teaching practice.
"It's very unsatisfactory for potential trainees and we are concerned they will be deterred from the profession because of the delay."
Schools which run initial teacher training are also affected. Martin Thompson, chair of the National Association of School-Based Teacher Trainers, said staff are "embarrassed" at having to explain the situation to applicants.
"Teachers can't make offers; it releases students into the job market," he said. "Schools don't know how they can plan for the start of the courses, which are really only seven months away."
A DfE spokesman said the allocations were delayed because ministers "needed to understand" the teacher supply model, which predicts how many training places are needed based on forthcoming school job vacancies.
"They need to be confident we have the right numbers, and are working as swiftly as possible," he said. "We are aware this is causing uncertainty. Students should continue signing up."
- Universities are training 32,162 would-be teachers on courses that began last September.
- 5,214 are training in schools and 551 are on the Teach First fast-track course.
- 51 per cent of all entrants to teacher training are over 25.
- The number of men entering primary teacher training has increased by 2 per cent in a single year to 18 per cent.