Facebook has urged ministers to reverse a ban on junk food advertising over fears it will scupper the social media accounts of thousands of small businesses.

The Silicon Valley giant has warned that a total online ban would inflict financial pain on bakeries, coffee shops and restaurants by stopping ads on their social media channels.

The call for a volte-face comes after Boris Johnson revealed in the Queen’s Speech last May that he would outlaw unhealthy food ads online and block them from TV before 9pm.

It attracted a backlash from the advertising and hospitality industry who accused ministers of piling pressure on small companies as they battled back from the pandemic.

Facebook could face the sharp end of the ban, with Deutsche Bank analysts estimating that small firms account for around three-quarters of its $70bn (£51bn) annual ad revenues.

A Facebook spokesman said: “Alongside industry trade bodies, and as part of regular meetings with officials on wider advertising matters, we have raised concerns about the impact of these proposals on small businesses.

“The measures would severely impact small businesses like bakeries, coffee shops and restaurants not only from advertising but even posting on their own social media accounts.

“We support the Government’s desire to reduce children’s exposure to the advertising of foods high in fat, sugar and salt, but believe online’s targeting capability can achieve this outcome.”

The Prime Minister committed to tackling Britain’s obesity crisis in June last year when he insisted the nation must get “fitter” in the wake of the pandemic.

About one in three children leave primary school overweight or obese, fuelling fears that it could cause an “obesity time bomb”.

The UK has the second highest obesity rate in Europe

Evidence suggests those who are heavier are also at greater risk of serious illness or death from Covid-19.

It is estimated that about £150m is spent on advertising by crisp, sweets and soft drink companies each year, with a significant slice paying for online ads.

A total ban on online adverts for junk food would see children eat the equivalent of 62 million fewer doughnuts a year, according to the Obesity Health Alliance.

Campaigners opposing the ban claim the Government’s own research shows such a move would only reduce a child’s calorie intake by 1.7 calories a day.

Adam Smith Institute, the neoliberal think tank, previously branded the ad ban as “nutty nanny statism” that was “savagely” striking at struggling hospitality businesses.

Meanwhile, the Federation of Small Businesses said earlier this year that the approach was akin to “using a sledgehammer to crack a nut” and would “jeopardise jobs and the recovery”.

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