David Hart, NAHT general secretary, has written to Education Secretary Charles Clarke twice this month seeking an urgent meeting and giving him an ultimatum over the agreement, which is supposed to reduce teachers'
workload by giving support staff greater roles.
An NAHT national council meeting has been called for January 27 and Mr Hart says it could decide to pull out unless members can be satisfied that the money is there for the agreement. "The prospects of withdrawal are very high because there are a large number of heads around the country who simply do not believe they have the funding in place to deliver the workload agreement," he said.
Mr Hart's letters also warn there is strong opposition from NAHT members to any attempt to limit funding for the progression of experienced teachers to level three of the upper pay scale.
Unions and ministers are locked in talks over the performance pay system after the School Teachers' Review Body rejected Mr Clarke's plan for a 30 per cent quota system for level three.
Mr Hart's second letter to Mr Clarke said the leaked workforce reform "blue skies" paper, revealed by The TES last week, which showed that a Department for Education and Skills official had considered reducing teacher numbers to cut costs, had only added to the NAHT's concerns.
There was no doubt that the DfES's thinking was "a fundamental reason for the failure to identify properly, and to our satisfaction, the costs of workload reduction," he said.
Peter Wilby 23; Letters 27