More than half of primary school teachers have spent their own money on resources for teaching reading and writing according to the survey commissioned by the Association of Teachers and Lecturers.

According to the survey, based on interviews with 340 primary teachers, the annual average spending on classroom materials is £28.50, with almost a quarter claiming to have spent over £50.

Peter Smith says teachers are "propping up" the government's plans for improving literacy

If these figures were applied to primary school teachers throughout the country, the union says that it would be the equivalent of an extra £5m for the education system.

The union's general secretary, Peter Smith, says that the survey reveals the insufficient support available for schools to introduce the government's National Literacy Strategy.

"Should fire-fighters buy their own hoses? Why should poorly-paid teachers have to pitch in with books?" said Mr Smith.

"Conscientious teachers felt they had no option but to prop up a key government policy by topping up the inadequate funding.

"The figures underline the intense personal commitment of teachers to get the best out of their pupils.