Mr Rosen said: “Those crucial years of four to six are when the picture book is the ideal reading and sharing material. These years have become clogged with anxiety, reading schemes, programmes, panic and the obsessive attention to individual letters.”

Huw Thomas, co-editor of Picture Books for the Literacy Hour, said that in some schools funding is being directed towards phonics rather than making sure children get good-quality picture books.

But Mr Thomas, who is also head of Emmaus Catholic and Church of England Primary in Sheffield, said: “I have always used picture books and I’m not sure picture books have been pushed out of schools to the extent of being killed off.”

Book Trust, the national charity, is promoting picture books through its Big Picture campaign, which is supported by illustrators including Shirley Hughes, Anthony Browne, Michael Foreman and Ken Wilson Max.

Anthony Browne, author and illustrator of Gorilla, Silly Billy and Into the Forest, said: “We think that growing up and being educated is about leaving things like pictures behind and moving into words. Children are encouraged to read books without pictures much earlier than they used to be. I’ve heard parents say, ‘Don’t get a picture book, get a real book’ - as if there is a difference. I think it’s a shame for children and for the country.”

Michael Foreman has illustrated more than 170 books, including Kensuke’s Kingdom by Michael Morpurgo. He said: “There have been one or two golden ages during my time but this is the first time there really is a serious threat, because there is less choice.

“It seems to me that if you’re not doing a book about snot, bogies or underpants, you have little chance of getting published. We need more poetic, different books that extend the child’s experience.”

A survey of 1,200 teachers by the UK Literacy Association earlier this year revealed that most primary teachers could not name more than three picture-book authors. Almost a quarter were unable to name a single one.