There will be a boost for fresh fruit and vegetables and deep-fried food will be banned in what the government has called the biggest shake-up to school dinners in England in over a decade.

Under new school food standards, fibre and wholegrains will also be increased, and breakfast clubs will have to follow nutrition rules for the first time, with schools also being monitored.

The Association of School and College Leaders (ASCL) welcomed the changes, but said they hoped the new rules would not become “another stick with which to beat head teachers”.

The changes will come into effect from 2027 and be funded with existing money for schools, the government said.

As part of the new framework, sweet desserts, like cake, will be reduced from a regular lunch offer to twice a week in secondary schools, and once a week in primary schools. They also must now be served with a portion of fruit.

Servings of processed meats such as ham, sausages and chicken nuggets have been reduced to once a week and must come with a side of vegetables or fruit.

Education Secretary Lucy Powell said they were “once-in-a-generation changes” which would “transform school food for children across the country”.

The Department for Education said it hoped the reforms would tackle childhood obesity, improve nutrition and support children’s concentration, learning and wellbeing.

Schools will be required to publish food policies and menus online with monitoring arrangements set to be developed alongside the Food Standards Agency, it said.

Pepe Di’Iasio, ASCL general secretary, said parents would feel “reassured” that schools were providing children with a healthy diet.

But on plans for enforcement, he added: “None of us would consider ourselves experts in health and nutrition. Don’t create another stick with which to beat head teachers when they are trying to do their very best to provide a healthy, balanced meal for those in our schools.”

He said schools needed “more investment” in catering facilities and in the “professional development” of school chefs to develop menus that “meet the ambitions” of the government.

As part of the changes, deep-fried chips will have to be oven-baked instead, and pasta dishes will need to be 50% wholewheat once a week. High-fibre bread will also become a requirement.

Breakfast clubs will undergo one of the biggest changes.

Historically, there has been no guidance on what they should provide, but from next September pastries and fried-eggs will be off the menu and there will be a sugar cap when it comes to cereals.

The government said Coco Pops would no longer be an option and chocolate spread was “not permitted”.

Since February this year, 1,250 schools have offered free breakfast clubs to their pupils.

One of those was Oasis Blakenhale in Birmingham, where principal Farzana Ahmed said the school welcomed the changes.

“The more children that can access a hot, nutritious meal, the better it is for us, the better it is for them, and actually it really supports families with the reduction of their financial pressures at home,” she said.

Ahmed said it was “important” that schools are monitored, but added that they “probably need some more guidance from the government on what that’s going to look like on a day-to-day basis”.

About 60% of pupils at the inner-city school receive free school meals, and Ahmed said they were already providing a healthy, balanced diet.

With free school meal eligibility expanding this year to all families who receive Universal Credit, Ahmed said there had been an “influx of parents” applying, and expects around 70% of pupils to benefit going forward.

“It’s a really positive move,” she said.

“We know how important a nutritional diet is to the wellbeing, to the behaviour, to the learning of our pupils.”

Working mum-of-three Kinza Butt said the free school meals her son was now getting at Blakenhale Juniors had lifted a “burden off the shoulders”.

“He doesn’t have to eat those cold sandwiches anymore,” she said.

“By the end of the day he used to be starving. But now he’s coming home all happy because he’s having good, healthy meals with a snack as well.”

The new food standards will apply to primary and secondary schools in England, but rules for school dinners vary across the UK.

In Wales, new guidance will come into force by the end of the year with a greater focus on at least two portions of vegetables being offered every day, with only water, milk or plant-based drinks allowed for hydration.

Scotland updated its legislation in 2020. It requires students to be offered at least two portions of vegetables and one portion of fruit every day and oily fish must be served at least once every three weeks.

Northern Ireland last updated its regulations in 2007. They include providing bread everyday, without spread, and offering two portions of fruit and vegetables a day. It also stipulates that if beans or pulses form the protein part of a main course, another vegetable must be available.