The Guardian has learned that under the proposals, children will only be able to drink water, skimmed and semi-skimmed milk, pure fruit juices, certain types of smoothies and yoghurt and milk drinks made with less than 10% added sugar.

Colas, all other fizzy, sugary drinks, and drinks with artificial sweeteners, will have to be removed, whether from canteens or vending machines. Sweets, chocolate, chewing gum, cereal bars, fruit bars and chocolate-coated biscuits will also be banned. Salty snacks such as crisps and salted nuts will go and salt will not be allowed on the table in school canteens.

A long list of junk food has been drawn up by a government-appointed expert review panel, whose report will be published in full next week. Ms Kelly will review the recommendations, which include the stipulation that certain foods should only be used sparingly.