The Government's £220m pledge to improve school meals is more than £550m too little, according to the School Meals Review Panel.
Analysis by accountancy firm PricewaterhouseCoopers (PwC), which forms part of the panel's report to Education Secretary Ruth Kelly, found that £782m was needed over three years to bring food up to scratch and refurbish kitchens.
PwC estimated that between £476m and £493m was required to implement the proposed Caroline Walker Trust (CWT) guidelines, while £289m had to be found to overhaul primary and secondary school kitchens.
"Some local authorities will increase the price of school meals to offset the difference," said a spokeswoman for the Local Authority Caterers Association (LACA). "But we are worried because some parents won't pay more and some can't."
She added that the problem was made worse because £90m of the proposed £220m was not ring-fenced specifically for improving menus. "That's why co-operation between all sides is vital," she said.
The report also compared English spending on CWT guidelines against Scotland's Hungry For Success programme. The Scottish Executive has injected £63.5m over three years into school meals and has ring-fenced a further £70m for the next 36 months.
PwC calculated that if the English sum were adjusted to mirror Scotland, the shortfall would be even greater. It found that £176m would be needed per annum for three years to implement the nutrient-based standards - a total of £528m.
"It's no surprise," said ex-LACA chairman Neil Porter. "We've been saying all along that the Government needed to spend roughly three times what it was planning to."
Private contractors have also expressed doubts about the lack of cash. A spokeswoman for Sodexho said: "We believe more money is required. If the report's recommendations are to be met, we believe in excess of 70p per pupil is needed."
A spokesman for the Department for Education and Skills (DfES) defended the spending commitment but hinted more money might be available later: "We've put in a lot of funding but it's very much a partnership approach. Local authorities, schools and other agencies must also play their part."
The Government will carry out an audit of school meals provision this month, which will look at overall funding levels. "We will review things over time. I don't envisage that it will be £220m and that's it," he added.
Government figures claim that 75% of parents were prepared to pay more for fresh food.
By Tom Bill