New laws to ban shops from offering special “two for the price of one” deals near supermarket checkouts for food high in sugar, fat or salt are to be introduced in an attempt to ease an obesity crisis that has made the UK the most overweight nation in western Europe.

Ministers will also announce today that they are to consult on introducing a 9pm watershed on television advertising for unhealthy foods after intense pressure from health experts. According to official figures, one in three children in the UK are now obese by the time they leave primary school.

After years of being criticised by health experts for failing to match its pledges to cut child obesity with action, the government will unveil a strategy that will also include:

• Forcing restaurants and takeaways to show the number of calories clearly on their menus.

• Consulting on a ban on the sale of energy drinks to children. Two in three children aged 10 to 17 use high energy drinks linked to numerous health issues in young people.

• Encouraging schools to adopt “active mile” initiatives, such as the Daily Mile scheme – which encourages nursery and primary school pupils to jog or run, at their own pace, for 15 minutes every day.

• Updating rules on the standard of food in schools so they reflect the most up-to-date sugar and fibre intake recommendations made by the Scientific Advisory Committee on Nutrition.

The measures were broadly welcomed by health organisations and experts, though some were privately disappointed that ministers had not committed to action on the television advertising watershed.

But industry leaders expressed “deep disquiet” at the prospect of further regulation from government. Tim Rycroft, director of corporate affairs at the Food and Drink Federation, said: “The government has come forward with proposals centred around further industry regulation. While the commitment to full consultation on these measures is welcome, there will be deep disquiet in the food and drink manufacturing sector today. Advertising and promotions underpin the healthy, vibrant and innovative market for food and drink that UK shoppers love.”

Experts also signalled that any backtracking or stalling would be disastrous for the nation’s health and the NHS’s finances.

Sir Harpal Kumar, Cancer Research UK’s chief executive, said: “More than 60 cancers are diagnosed daily in the UK due to excess weight, and our research has shown that young people are more than twice as likely to be obese if they remember seeing a junk food advert every day.

“Children who carry too much weight are five times more likely to be obese adults, putting them at risk of many diseases, including several types of cancer. The government now needs to be steadfast in taking forward these measures with urgency and determination.”

Government sources conceded that after years in which ministers had been preoccupied with structural changes to the NHS – most of which failed to deliver real savings – it was now widely accepted within Whitehall that effective campaigns to improve public health, notably by tackling obesity, were a far more effective way to control NHS costs.

Health secretary Jeremy Hunt said: “It is near impossible to shield children from exposure to unhealthy foods. Parents are asking for help – we know that over three quarters of parents find offers for sugary sweets and snacks at checkouts annoying. It’s our job to give power to parents to make healthier choices, and to make their life easier in doing so.”

The government will also call on industry to recognise the harm that constant adverts for foods high in fat, sugar and salt can cause, and look at introducing incentives to those that reduce the sugar and calories in the products they sell.

Last November the Organisation for Economic Co-operation and Development (OECD) found that 26.9% of the UK population had a body mass index of 30 and above, the official definition of obese in 2015. Only five other OECD member states had higher obesity rates, four outside Europe and the other in eastern Europe. The OECD pointed out that obesity had increased by 92% in the UK since the 1990s.

Caroline Cerny of the Obesity Health Alliance representing groups concerned about obesity,said that the plans had “the real potential to ensure that children in the UK will face the healthy future they deserve. For too long our environment has continually steered us towards high fat and sugar options with relentless advertising and promotions.”

She said the plans did address the issue of children “being continually exposed to junk food adverts when they watch their favourite TV shows and when they go online. These proposed measures, along with action on the promotion and placement of unhealthy food and improved labelling, demonstrate that the Government is stepping up to create a more balanced environment that will make it easier for everyone to make healthier choices.”

The Local Government Association, whose members are responsible for public health, welcomed the plan but said more needed to be done, including giving councils powers to ban junk food advertising near schools and the need for specialised support for obese and seriously obese children.

“Councils need to be properly resourced if they are to carry out their public health responsibilities effectively and this needs to be balanced against their already over-stretched budgets, otherwise the ill health consequences of obesity in our younger generation risks causing NHS costs to snowball.”

Professor Graham MacGregor, chairman of Action on Sugar and of Action on Salt said: “What’s missing is a fully joined-up campaign which includes: uniform traffic light labels on food, rather than just calorie labelling, mandatory reformulation on sugar and calories, a tax on confectionery or unhealthy food with the opportunity to reformulate, and only healthy products (not high in fat, salt and sugar)should be marketed across all platforms, including TV, digital and print marketing. Simply consulting about the nation’s biggest public health crisis is not going to save lives.”