A ban on confectionery, crisps and fizzy drinks being provided in schools looks certain to begin in September following the publication of advice to ministers by the new School Food Trust yesterday.

The food industry has been lobbying to water down tough proposals on school food put out for consultation by the Department for Education and Skills last autumn.

But the trust, which was set up by the education secretary, Ruth Kelly, in the wake of chef Jamie Oliver's acclaimed TV series on the subject, has ruled that new standards must apply to all food provided in schools including vending machines, tuck shops and cafeterias.

Dame Suzi Leather, the trust's chairwoman, said: "New food standards from September will improve school meals, but they cannot succeed if pupils are surrounded with chocolate, crisps, and drinks that fill them up with sugar and fat during the school day.

"One in eight of our children is now obese. Anecdotal evidence suggests that, when these products are removed, behaviour also improves."

The trust received evidence from representatives of the food industry and vending machine companies which argued that "healthier" snacks and fizzy drinks should be allowed.

The trust decided that would cause confusion, would not contribute to education about good food and would increase dental erosion.

The new standards are expected to be agreed by Ms Kelly and will recommend:

· No confectionery should be sold in schools

· No bagged savoury snacks other than nuts and seeds - and these must be without added sugar or salt

· A variety of fresh fruit and vegetables should be available

· All children should have access to fresh free chilled water at all times, and this should not be in the toilet block

· The only other drinks available should be bottled water, low fat milk, pure fruit juices, yoghurt and milk drinks with less than 5% sugar, or drinks made from these such as smoothies, tea or coffee. Artificial sweeteners will be allowed but only in these types of drinks

The advice does not apply to lunchboxes or fundraising events.

The advice will have a major impact on the vending industry. A recent survey carried out in Oxfordshire by the department of public health at Oxford University found that 95% of all vending machine products considered "less healthy" would no longer be allowed under the trust's rules. School vending machines have an estimated annual turnover of £45m.

Joe Harvey, head of the Health Education Trust and a member of the School Food Trust, said he was relieved that tough standards were in the final advice. "We still want artificial sweeteners removed, but it's a brilliant result."

The Jamie Oliver effect

Jamie Oliver's Feed Me Better campaign focused concern on school meals and put on unprecedented pressure to improve standards. Channel 4's TV show, Jamie's School Dinners, in February 2005, featured Kidbrooke school in the London borough of Greenwich, and tackled children's understanding of what they eat - most memorably when Oliver showed a class the fat, gristle and skin in chicken nuggets by whizzing them in a food processor to produce a repulsive runny pink paste. His menus exposed the dinner ladies' lack of training and understanding of nutrition. Soon after, a 271,677 signature petition was presented to No 10, and the government agreed a £220m budget rise. Greenwich rolled out Oliver's menu to all its 56 schools.

Robert Booth