The BBC's Mike Baker: "Inspectors say a minority of schools have not made much progress"

The prime minister was speaking after a report found that a pilot of the government's literacy strategy had generally improved children's reading and writing in primary schools - but also that results varied widely between schools.

In a minority of schools, teachers are said to be struggling to grasp the new teaching methods that have been introduced. Others are reported to have expectations of pupils which are too low.

Mr Blair said there were "still too many schools where we don't have an absolute drive for excellence".

Tony Blair: "Nothing a teacher does is more important than teaching a child to read and write"

"I am told that inspection reports show that children in some schools are taking only eight weeks to learn the letter sounds of the alphabet, while in other schools it takes two or even three years," he told a London conference on the teaching of reading.

"Nothing a teacher does is more important than teaching a child to read and write, yet the differences in capacity are frighteningly large.

"The price of failure can only be described as catastrophic.

"Children switch off. They see books, and therefore learning, as a drag. Their vocabulary and understanding is limited to what adults with whom they mix tell them.

"And if they don't - as many don't - have an adult to read to them, the whole business of learning passes them by."

David Blunkett: "For the first time in 30 years, structured teaching of English is at the core of our strategy"

The National Literacy Project, carried out over the last two years in 18 English education authorities, has seen the introduction of teaching methods designed to raise standards in the early years of primary education.

These include an emphasis on the use of phonics (the sounds of letters), spelling, grammar and the use of a dedicated daily literacy hour.

Under the new banner of the National Literacy Strategy, the project was extended to include the rest of England at the start of the current school year.

It is the centrepiece of the government's attempts to ensure that 80% of 11-year-olds are achieving the standards expected for their age by the year 2002. This year, 65% of the age group reached this level.

Teachers' union leader Nigel de Gruchy: "We were told it was going to guarantee against poor teaching"

The report on the pilot programme was published by the Office for Standards in Education (Ofsted).

The Chief Inspector of Schools in England, Chris Woodhead, said "very promising progress" was being made in the majority of the project schools.

"Problems have occurred when, first, the headteacher has failed to drive the project forward through knowledgeable and committed leadership and, second, when the teachers simply do not understand how to teach phonics in a structured and stimulating way."

At the conference, the Education Secretary, David Blunkett, announced that local education authorities would receive an extra £54m next year to help them implement the literacy strategy.

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