Jamie Oliver has hit out at a fresh review into school dinners, warning it is time for action and not more "costly reports".
The TV chef said he feared that the government-commissioned inquiry is "destined to be ignored" by ministers.
Education secretary Michael Gove announced on Wednesday that Henry Dimbleby and John Vincent, the men behind the Leon restaurant chain, are to lead a review into food in England's schools.
It comes amid concerns that many youngsters are still being served unhealthy meals, and that more needs to be done to boost food standards in all schools.
Oliver, who led a campaign seven years ago to improve school lunches, raised concerns that ministers are dragging their feet over taking action.
He said he was confident that Mr Dimbleby and Mr Vincent will do a "thorough job" on the review.
But he added: "Now is not the time for more costly reports. Now is the time for action and that doesn't seem to be what we get from Mr Gove when it comes to school food and food education.
"This just delays action for another year or more."
Oliver said it was "ironic" that the education secretary had announced the review at a school with a kitchen garden that has a dedicated caterer making fresh meals on-site.
"This simply does not reflect the current resource and reality in most schools around the country," he said.
"I believe these things urgently need to be the norm in schools - along with support for good school food and further training in the school food service.
"I'm fairly confident that the gentlemen from Leon will end up pushing for the same things that I, and many others, have been pushing for years, but the question is, will Mr Gove listen? Will he finally do anything about the problems in school food?
"Is it too much to ask for a government which listens and which sees the ill-health of our country's children as a major challenge to be met with important, sustainable policies to actually solve the problems?
"Will this be just another report by good people which is destined to be ignored? I hope not but I fear it."
The new review, which was welcomed by campaigners, will investigate school dinners across the country, and establish an "action plan" on how all schools can improve food standards.
It will involve looking at the factors which influence the choices schools make about food, the DfE said.
Mr Gove said: "There has been an improvement in school food in recent years with many schools transforming school dinners, introducing food growing into the curriculum and teaching cookery.
"However, there is still more to do particularly in taking localised successes and ensuring they are replicated nationally."
According to School Food Trust (SFT) research, primary age children now eat an average of 1.6 portions of fruit and vegetables in their school lunch, with 35% consuming at least two portions.
In secondary schools, pupils eat an average of 0.8 portions of fruit and vegetables at lunchtime.
The Department for Education (DfE) also cited a small-scale survey of around 80 secondaries which showed that 22.5% provided at least one portion of vegetables or salad per pupil every day.
SFT chief executive Judy Hargadon said they were "delighted" that Mr Dimbleby and Mr Vincent are leading the review.
"Even aside from the proven benefits of good school food for children's behaviour and concentration, it has such enormous potential to improve public health. With one in three children overweight or obese by the time they leave primary school, we have to make sure this is being fully realised.
"We agreed with government a long time ago that the sensible time to launch a review was following completion of our study of food in secondary schools.
"In assessing all the progress that's been made, the key thing here is deciding how best to help our schools and caterers keep that progress going."
Mr Dimbleby and Mr Vincent are due to report back with their findings next year.
Ministers said that in the seven years since Oliver's campaign for healthy dinners there has been a "measurable improvement" in the nutritional quality of the food and in the numbers eating school meals.
This is due to the work of many people, the DfE said.
Oliver's campaign led to junk food being banned from school canteens and vending machines.
Strict nutritional guidelines were made compulsory in primary schools in 2008 and the same policy was introduced in secondaries in 2009.
But last year, the TV chef raised concerns that academies were exempt from these guidelines, and in May he said that children's future health was being put at risk.
The warning came as SFT research showed that over one in four academies are offering crisps and savoury snacks, while around one in six are providing chocolate and sweets.
The TV chef said that the research has provided "solid evidence" for the first time that nutritional food standards in academies are in danger.
Mr Gove has always maintained that giving academies the choice to opt out of nutritional standards gives them the freedom to do what is best for their students, and said there is no reason to believe these schools will not provide meals that meet the regulations.
Around half of secondaries now have, or are in the process of getting, academy status, which gives them more freedoms than other state schools.
Shadow children's minister Sharon Hodgson said: "We don't need another review of nutrition in schools - we already have a comprehensive set of standards developed by experts and implemented across our schools under a Labour government thanks to the hard work of catering staff and commitment from school leaders.
"The real problem is that Michael Gove has deliberately exempted academies and free schools, in which more than a million children and rising are taught, from those standards.
"If he is serious about improving the health and educational outcomes of children then he needs to perform another U-turn and bring back healthy food standards in all schools rather than just spending more time on another review."