Supermarkets are being warned by the Government not to sell sweets and chocolate at checkouts.
The Department of Health has told retailers it wants to see "real action" taken on the issue after evidence that foods sold at "impulse purchase points", such as tills, saw a significant increase in sales.
Recent research by the campaign group Junk Free Checkouts has found that 83% of parents have been pestered by their children to buy sweets at the checkout - and 75% admit to having given in.
Some 93% of those asked said they believed selling junk food in supermarket checkout lanes contributed to obesity and the majority said retailers should be asked to stop doing it.
Citing the research, public health ministers Jane Ellison said: "There is evidence that the majority of food promoted at checkouts and in queuing areas is less healthy than elsewhere and that foods sold at impulse purchase points such as checkouts experience uplifts in sales."
She added: " … parents have indicated that positioning of sweets at checkouts can increase pestering to purchase by their children."
It represents a significant shift in position for the Government, which last year ruled out taking action against retailers who promoted junk food in so-called "guilt lanes".
The then public health minister, Anna Soubry, dismissed the idea saying she had managed to say "no" to her children.
However, following Ms Ellison's comments, a department of health spokesman said: "We have specifically discussed this important issue with supermarkets and will be looking to them to take real action on it.
"While we have been clear that legislation is not necessary and that the voluntary approach through the Responsibility Deal is working, we are taking this issue very seriously in our discussions with the industry.
"The Responsibility Deal has set-up consistent front of pack food labelling which all the major supermarkets and several big manufacturers have signed up to. It has also significantly reduced artificial trans-fat, calories and salt in foods."
The Junk Free Checkouts campaign, which launched last month, is run by the British Dietetic Association's (BDA) Dietitians in Obesity Management Specialist Group (DOM UK) and the Children's Food Campaign.
Speaking at the launch, BDA obesity specialist Linda Hindle said: "Unplanned calories from foods high in fat and sugar purchased at checkouts contribute towards poor diet and poor health, including obesity, heart disease and diabetes, which may lead to premature death.
"Eating sugary or acidic food and drink also directly contributes to tooth damage. Although dental decay is completely preventable, one third of 12-year-old children have a filled or extracted tooth, a sure sign that the rot of poor diets is already setting in.
"Far too many retailers are unwilling to stop pushing unhealthy food at the checkout and queuing areas. It may be lucrative for them but, as our survey found, it is deeply unpopular with customers and nudges purchasing behaviour in the wrong direction. If retailers can’t act on their own, then we hope to see robust action from the government to tackle this problem."
Following a campaign against the sale of junk food at supermarket tills in 2003 a number of retailers reduced the number of sweets and chocolates on offer and replaced them with healthy foods.
However, the changes have not lasted and the unhealthy snacks have returned.