More and more children are starting school without being able to communicate properly or even use the toilet, the head of Ofsted is due to warn.

Amanda Spielman will use a speech to nursery leaders in London today to highlight the rising number of youngsters who lack basic hygiene and language skills by the age of 4.

It follows a survey this week, which found that millions of hours of teaching time were being lost because children are turning up to school unable to wipe their own bottoms.

The chief inspector will urge nursery staff to play their part in helping children learn these skills, saying they can “make a world of difference”.

Ms Spielman’s speech is expected to describe some children as “lucky” - those who are given bedtime stories or taught the alphabet by their families.

Others, she will say, are “unlucky”, and do not get the same help at home.

“We now have a situation where, aged 4, some children have less than a third of the English vocabulary of their peers,” she will tell members of the Pre-School Learning Alliance.

“These children arrive at school without the words they need to communicate properly. Just imagine the disadvantage they face, right from the start.

“Unable to follow what’s going on. Unable to keep up with their classmates. Unable to reach their potential.”

She will encourage daycare staff to spend time teaching pre-school children new language skills - whether through songs, nursery rhymes or “time-honoured classics” such as Hans Christian Andersen or Dr Seuss.

“We know that at the most basic level, poor literacy holds a person back at every stage,” she will add.

“As a child, you will do worse at school. As a young adult, you may struggle to find work. And as a parent, you won’t be able to help your own children learn. This is a vicious cycle.”

Ms Spielman will also highlight a recent study that found 70 per cent of schools reported more children starting school without being toilet trained compared to five years ago.

Describing this skill as a “simple, but necessary, expectation” for four-year-olds, she will describe how a lack of toilet training can not only be disruptive for teachers, but can also have a negative effect on a child as they start school.

“I am not suggesting nurseries are substitute parents,” she will stress.

“Nor do I think children should start reception as perfectly well-turned-out mini adults, who always go to the toilet unaided and never have accidents.

“But we know that the best nurseries work closely with families, helping to establish simple routines, such as sleep time and potty training, as well as introducing children to foods that they may refuse at home.”

The Ofsted head will say children starting their first year of school should also be able to sit still and listen, understand the words “no” and “stop”, and be able to put on their own shoes and coat.