Unhealthy food may have to carry warnings that it is "high fat" or "high in sugar", as part of an attempt by the Government to tackle obesity.
Melanie Johnson, the Public Health minister, will warn manufacturers and fast-food chains today that they must cut the amount of fat and sugar in their meals or the Government will bring in compulsory labelling or laws curbing unhealthy ingredients.
At an "obesity summit" attended by the chief medical officer, Sir Liam Donaldson, and food manufacturers, Ms Johnson will urge food manufacturers to take responsibility for the nation's diet.
Doctors have warned that one in three adults in Britain will be obese by 2020 unless urgent action is taken. Obesity contributes to heart disease, diabetes and other serious ailments. Two government documents, published at the Food and Exercise Summit, will threaten to use the law to force manufacturers and fast-food chains to reduce levels of fat and sugar in food if they fail to take voluntary action.
"We have seen some voluntary action but we want to see more from the industry," said one government source.
Ministers will also stress that individuals should take responsibility for their own health. They believe education about healthy eating is the key to cutting obesity but consumers should be informed about the content of food.