Some schools are still failing to meet strict new rules on healthy dinners, an Ofsted report has found.

And parents from low income backgrounds are struggling to find the funds to pay for their children to eat school lunches, it says.

More than one in three schools visited by inspectors are not complying with standards introduced two years ago in primaries and nearly a year ago in secondaries, the report shows.

Of 39 primary, secondary and special schools visited, plus one pupil referral unit, 24 (62%) were meeting or close to meeting the food-based and nutrient-based standards. It means that 38% of the schools were failing to comply. More primary than secondary schools were meeting the standards, possibly because their rules have been in place longer, inspectors said.

The mandatory nutrient standards mean that an average school lunch must now contain at least one portion of vegetable or salad, and one portion of fruit. Fat, sugar and salt is restricted and each meal must contain minimum levels of nutrients including iron, zinc, calcium and vitamins.

The report reveals concerns that parents who are on low incomes but are not eligible for free school meals (FSM) are struggling to find the money to pay for their children to be fed at school. In one case two children from one family had to take it in turns to have lunch, it says. Children are eligible for FSM if their families receive benefits or have an annual income of less than £16,040.

The report said: “A more difficult area to tackle for the schools and authorities visited was the take-up of school meals by families whose income was low but who were above the threshold for being entitled to free school meals.”

Families in this situation, with a lack of transport, are reliant on a cheap range of food available nearby that is not always healthy, it said.

The report did find that most pupils have a good understanding of what a healthy diet is, and in most schools the food is nutritious and well prepared. Many offer meal deals, tasting events or theme days to encourage youngsters to take up the dinners.

Ofsted director of education and care Patrick Leeson said: “This report shows the encouraging progress schools are making to promote healthy eating, meet nutritional standards and make good school meals affordable. Children need good food at school to support their progress and achieve high standards of learning.”