Advertising unhealthy foods during family TV shows should be banned, MPs have said, as they called on the Government to introduce a "sugar tax" on soft drinks.
In a wide-ranging report, members of the Commons health committee said the Government must not "take the easy option of relying on health education campaigns" and promoting exercise to solve the UK's obesity crisis.
Instead, they said something "far more ambitious" was needed, calling for Jamie Oliver-style graphic warnings on the side of fizzy drinks saying how many spoonfuls of sugar a single serving contains.
Furthermore, a 20% tax on full sugar soft drinks should be introduced, with all the money raised spent on preventing childhood obesity.
Oliver is taking part in a discussion at parliament, designed to coincide with the publication of the committee's report, ahead of a debate on a tax for sugary drinks.
The chef will join Helen Jones, chairman of the petitions committee, and Dr Sarah Wollaston, chairman of the health committee.
Other recommendations in the report include a ban on unhealthy food advertising before the 9pm watershed during TV programmes enjoyed by families, such as the X Factor.
Buy-one-get-one-free and other deals on unhealthy foods in supermarkets should also face "strong controls", with an outright ban on supermarkets placing sweets and other less healthy foods at the ends of aisles and checkouts.
New guidelines must also be drawn up on what constitutes a healthy school packed lunch, with teachers able to guide those parents who continue to give their children unhealthy foods.
The use of cartoon characters and celebrities in children's advertising should also face tighter restrictions, while rules that claim a breakfast cereal which is 22.5% sugar is not a high sugar food must be changed, the report said.
While the food industry should be invited to join voluntary "reformulation" schemes to drive down the amount of sugar or fat in their foods, it must be made clear that a failure to comply would lead to enforced regulation, the MPs added.
The new report follows a row between the health committee, Health Secretary Jeremy Hunt and Public Health England (PHE) about recommendations in a PHE report suggesting a sugar tax be introduced.
PHE originally refused to publish its report proposing a sugar tax until the Government published its own strategy next year, but reversed that decision in the face of mounting pressure.
Prime Minister David Cameron is known not to be in favour of a sugar tax.
In the new report, MPs said they agreed with the PHE study that there must be "broader and deeper controls on advertising and marketing to children".
They said: "In our view, a logical way to do this would be by restricting all advertising of high fat, salt and sugar foods and drinks to after the 9pm watershed.
"We also endorse Public Health England's recommendation of extending current restrictions on advertising to apply across all other forms of broadcast media, social media and advertising, including in cinemas, on posters, in print, online and advergames."
The MPs also called for smaller portion sizes, saying they are becoming "larger and larger", for example the introduction of "bottomless cups" in restaurants.
New figures last week showed a third of 10 and 11-year-olds in England are overweight or obese, although obesity among younger children is falling.
Sugar-sweetened drinks currently for 29% of sugar intake among children aged 11 to 18, and around 16% for younger children.
Treating obesity and its consequences currently costs the NHS £5.1 billion every year.
Chair of the health committee, Dr Sarah Wollaston, a GP, said: "We believe that if the Government fails to act, the problem will become far worse. A full package of bold measures is required and should be implemented as soon as possible.
"We believe that a sugary drinks tax should be included in these measures with all proceeds clearly directed to improving our children's health."
A coalition of almost 20 groups has also been formed to demand a 20% sugar tax and further action. Members include the Academy of Medical Royal Colleges, the British Heart Foundation, the British Medical Association, Cancer Research UK and the Faculty of Public Health.
Kawther Hashem, nutritionist and researcher at the campaign group Action on Sugar, said: "Parents and children are currently drowning in a world full of aggressively marketed and promoted sugary foods and drinks.
"It is high time the Government took responsibility for the health of the nation and set sugar reduction targets and rules on all forms marketing and promotion of unhealthy foods and drinks."
Chris Askew, chief executive of Diabetes UK, said: "We support calls to introduce a tax on drinks high in sugar, reducing and rebalancing the number and type of the price promotions on unhealthy foods and setting national standards for healthy foods in the public sector.
"The Government should also continue to invest in educating the public about healthy living and making it easier for people to be more physically active."
Tam Fry, from the National Obesity Forum, described the report as a "breath of fresh air".
He said: "If the Government follows this, we will be strides ahead in solving the obesity problem."