Moving through the new pay threshold will give teachers an extra �2,000 straight away - or backdated to September 2000 if it takes longer than that to process the applications.

After at least two years on the new scale, teachers will be able to apply for further rises of up to �1,000 if they can show "substantial and sustained achievement".

The total of these increases will be �4,000.

In theory then a classroom teacher could, without taking on extra responsibilities, move from the current maximum of just under �24,000 a year to around �30,000.

But only after many years.

The School Teachers' Review Body, the independent body which makes recommendations on pay in England and Wales, sought to reconcile the views of the education secretary and the various education unions on how the upper pay scale would work.

In the event it said - and David Blunkett accepted - that there should be "a range of four points above the threshold uplift".

"We would not expect such points to be awarded annually other than in exceptional circumstances," it said.

There is to be further consideration of how the new pay scale will work in practice - and of the tricky subject of extra pay points being withdrawn "in the event of a significant deterioration in performance".