Ready meals, pizzas, burgers, savoury snacks and sandwiches are likely to targeted in a drive to tackle childhood obesity.
A year after the launch of a landmark plan to tackle the crisis, leading figures say a "much more robust" strategy is needed to ensure targets are met.
Public Health England (PHE) says "real progress has been made" on reducing sugar levels in many products.
According to PHE, one in three children are either overweight or obese by the time they leave primary school, while recently released figures showed that more than 600 children and young people under 25 were treated for type 2 diabetes in 2015/16 - nearly 80% of whom were obese.
PHE said it will be focusing on the reduction of excess calories in a range of products in conjunction with the implementation of the soft drinks industry levy, which will come into force in April 2018.
The levy, or sugar tax, will create an additional charge for drinks manufacturers whose products exceed around 5% sugar content.
But the Obesity Health Alliance (OHA), a coalition of more than 40 leading health charities, medical colleges and campaign groups, said that "despite some good progress", its assessment of the plan was: "Must try harder."
It warned that the guidelines should be extended to include saturated fats, along with measures to reduce the impact of junk food marketing where children were the target audience.
OHA alliance lead Caroline Cerny said: "Good progress has been made over the last year with strong measures to reduce sugar from foods and drink and we look forward to seeing ambitious targets for industry to make the food we eat less calorific.
"However, we can't ignore the fact that the food industry continues to get away with bombarding children with adverts that we know encourage unhealthy food choices.
"Failing to tackle this area is significantly undermining the impact of the childhood obesity plan."
Graham MacGregor, professor of cardiovascular medicine at Queen Mary University of London, and chairman of campaign group Action On Sugar, said: "We need a much more robust plan with enforcement of the sugar and calorie reduction targets, at the same time, the sugar-sweetened soft drinks levy needs to be extended to confectionery, the second biggest contributor of energy intakes in children.
Mr MacGregor also criticised Theresa May for having "watered down" the childhood obesity plan "for entirely political reasons" since its inception by David Cameron's government.
PHE said it will now undertake a period of detailed consultation with leading foods and drinks businesses to formulate a plan that would best enable them to reach the target 20% sugar reduction in key foods by 2020.