In his annual lecture, the head of the Office for Standards in Education claimed that 40% of pupils were leaving primary schools "illiterate" and called for an acceptance that teaching standards have to be upgraded.

"Any serious discussion of teachers and teaching must begin with an honest recognition that standards are too low in too many schools.

Successful teachers are praised, but Mr Woodhead accuses many teachers of low standards

"Too many teachers do not know enough about the subjects they teach, do not have high enough expectations of the progress their pupils ought to make, do not have a firm enough grasp on what needs to be done - lesson by lesson, week by week - if this progress is to be achieved."

In a message likely to provoke an angry response from teachers' unions, Mr Woodhead said that the evidence for the need for improvements was apparent in "underachievement on a massive scale".

"The fact remains that about 40% of children leave primary school to a greater or lesser extent illiterate and innumerate," Mr Woodhead claimed.

While applauding the achievements of successful teachers, the chief inspector accused some teachers of being resistant to change.

Teachers' union has "no truck with democracy"

Teachers have to accept the right of the government to impose changes such as the national curriculum and the regulatory system operated by Ofsted, Mr Woodhead said, rejecting arguments from teachers that there is too much interference in the running of schools.

The National Union of Teachers' opposition to the government's proposals showed that they do not "have much truck with democracy".

In a speech that follows the publication of primary school league tables showing that there are still weaknesses in English and maths, Mr Woodhead backed the government's drive to raise standards.