Adverts for junk food are to be banned on the entire Transport for London (TfL) network to help tackle childhood obesity, Sadiq Khan has announced.

From February, promotions for unhealthy food and soft drinks will be stripped from trains, buses, boats and trams across the capital.

The decision covers the likes of fizzy drinks, chocolate bars, and cheeseburgers, meaning big brands like McDonald's and Cadbury will only be able to feature healthier products on any adverts they want to run.

Mr Khan, London's mayor, said a public consultation launched in May had found "overwhelming support" for a ban, which will apply on all modes of transport controlled by TfL.

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Image: Food like pizza and burgers will be covered by the ban

He added: "Child obesity is putting the lives of young Londoners at risk and placing huge pressure on our already strained health service.

"It is absolutely imperative that we take tough action against this ticking time bomb now, and reducing exposure to junk food advertising has a role to play in this - not just for children, but parents, families and carers who buy food and prepare meals.

"It's clear that advertising plays a huge part in the choices we make, whether we realise it or not, and Londoners have shown overwhelming support for a ban on adverts for junk food and drink on our transport network.

"It's completely unacceptable that in a city as prosperous as London, where you live and the amount you earn can have a massive impact on whether you have access to healthy, nutritious food. I'm determined to change this."

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Image: Sadiq Khan said the decision was backed by most Londoners

The capital has one of the highest child overweight and obesity rates in Europe, with almost 40% of children aged 10 and 11 overweight or obese.

Children from more deprived areas are more affected, with young people in Barking and Dagenham almost twice as likely to be overweight as children from Richmond.

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And this week, new figures from Diabetes UK revealed nearly 7,000 young Britons now have Type 2 diabetes, which is linked to obesity.

That followed a report published by Cancer Research UK earlier this year, which found young people who recalled seeing junk food adverts every day were more than twice as likely to be obese.

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Mr Khan also announced that he wanted to ban to encourage the advertising of good food and a healthy lifestyle on the network, rather than there be no food and drink promotions whatsoever.

It is part of a wider initiative to halve the number of overweight and obese schoolchildren in London by 2030 - and to reduce the gap in obesity rates between the richest and poorest areas.

The mayor has also proposed that new hot food takeaways be banned from opening within 400 metres of schools.