London, March 6 (IANS): The portion sizes of some of Britain's most popular foods are to be cut, with health officials telling the public it is time "to get on a diet", a media report said on Tuesday.

Public Health England (PHE) is targeting pizzas, ready meals, processed meat and takeaways, in a new obesity drive, the BBC report said.

The government agency has also urged the food industry to start using healthier ingredients and encourage the public to opt for lower calorie foods.

It is all part of a drive to cut calorie consumption by 20 per cent by 2024.

The target will apply to 13 different food groups, responsible for a fifth of the calorie intake of children.

"Britain needs to go on a diet. Children and adults routinely eat too many calories, and it's why so many are overweight or obese," the BBC quoted PHE Chief Executive Duncan Selbie as saying.

If action is not taken, PHE said, it would be prepared to ask the government to legislate.

The agency would be strictly monitoring progress by looking at which products people were buying and would be prepared to "name and shame" individual companies not pulling their weight.

It will also launch a campaign encouraging adults to consume 400 calories at breakfast and 600 each at lunch and dinner.

It is recommended that women should eat no more than 2,000 calories a day, while men should limit their intake to 2,500.

For children, it varies depending on age.