The Department for Education and Employment is funding an extra 350 places on courses for returning teachers, on top of the 225 places already allocated to the capital this year.

Returning teachers will get a bursary of up to pound;1,500 during the six-to-12-week refresher training courses, while the training institutions will get pound;500 per recruit.

Those who take up the places must do their school placements - of at least 10 days - in boroughs involved in the Government’s Excellence in Cities initiative. These include muchcriticised education authorities such as Hackney and Islington, as well as successful ones such as Camden.

So far, 210 placements have been organised in 12 London boroughs, though there are not yet returners to fill them.

London and the South-east are bearing the brunt of the teacher-recruitment crisis. An estimated 10 per cent of London posts, around 4,000, are being covered by supply staff.

Meanwhile, members of the National Union of Teachers have sent postcards to Education Secretary David Blunkett, asking him to make it a happy new year by raising London allowances and bringing back recruitment and retention allowances.