The letter to Education Minister Nadhim Zahawi has been signed by over 250 people working in children's education, including primary school headteachers, academics and children's author Michael Rosen.

It calls for "vital improvements" to be made to England's education curriculum, with more time spent on reading comprehension and on encouraging children to be motivated to read and less time spent on phonics.

"Teachers should be supported to use a range of phonics teaching approaches, not just synthetic phonics", the letter adds.

"Robust evidence also suggests that the DfE should... decrease the amount of time devoted to phonics teaching in the national curriculum."

These changes, as well as an "evidence-based approach" are needed "urgently" if more children are to succeed, adds the letter.

'Synthetic phonics' is a way of teaching children to read by recognising that combinations of letters make sounds, and then combining these sounds to spell out words.

Youngsters in England spend much of their time spent learning literacy in their first few years at primary school being taught the approach.

The letter also demands that the phonics screening test be scrapped.

This is a test given to children in year 1 to assess their reading development.

'No evidence'

The letter says: "Teachers are better placed to decide which resources to use to support their teaching of reading, and how to assess children's early reading development."

It comes as a major new study by UCL - co-authored by two signatories to the letter - says there is no evidence that the current focus on phonics is the best way to teach children.

Co-author of the research Professor Dominic Wyse, of UCL's Helen Hamlyn Centre for Pedagogy, said: "The system doesn't give teachers enough flexibility to do what they think is best for their pupils, nor to encourage pupils to enjoy reading."

Teaching children to read is "crucial to improving their life chances", he said, adding that his research shows the current policy is "uninformed" as "it is not underpinned by the latest robust evidence".

'Phonics provides a strong foundation'

Julie McCulloch of the Association of School and College Leaders said was important that the use of phonics is "combined with approaches which help children to appreciate stories and develop a love of reading".

But she added there was "clear evidence that synthetic phonics provides a strong foundation" in learning the skill.

A Department for Education spokesperson said: "We are committed to raising literacy standards by following the evidence. Systematic phonics teaching has been proven the world-over to be the most effective method of teaching children to read.

"Since the introduction of the phonics screening check in 2012, the percentage of Year 1 pupils meeting the expected standard in reading has risen from 58% to 82%."

The spokesperson added: "Phonics is just one part of becoming a fluent reader. As well as systematic phonics teaching, teachers should also focus on speaking and reading stories to foster a love of reading among children."