Health charities are calling for advertisements promoting junk food to be banned from television before 9pm in a bid to tackle obesity.

Leading researchers and more than 47 health charities said adverts for food and drink containing high levels of fat, salt or sugar should no longer be shown before the watershed.

It comes as a recent Public Health England (PHE) report found that being obese increased the risk of dying from coronavirus by 27%, while being morbidly obese more than doubled the risk.

Action On Sugar, Action On Salt and 47 other health charities have now urged the Prime Minister Boris Johnson to implement all outstanding recommendations from the Government’s childhood obesity prevention plan, published in 2016.

But they warned if future plans exclude restrictions on junk food marketing, the measures will “not deliver the necessary impact” to public health.

The Government is said to be working on a new programme to tackle obesity ahead of a possible second wave of coronavirus in the UK, the Guardian reported on Saturday.

Mhairi Brown, policy and public affairs manager at Action On Sugar, Action On Salt, said: “In order for the Prime Minister’s new obesity plan to be effective and change the health trajectory of future generations, a robust and joined up policy package is required rather than a pick and mix of measures which allow loopholes to be exploited.

“With inequalities once again brought to the forefront as a result of Covid-19, Mr Johnson has a golden opportunity to ensure that lessons learned during the pandemic are translated to equitable access to health for all.”

Evidence submitted to a Government consultation on the issue in 2019 demonstrated that a ban would encourage the food and drink industry to improve the nutritional quality of their products so they could be advertised again, the charities said.

John Maingay, director of policy and influencing at the British Heart Foundation, said: “This analysis shows that while some progress has been made towards addressing childhood obesity, crucial measures have not yet been embraced by the Government.

“Most notably, we are concerned that the introduction of a 9pm watershed on junk food marketing is slipping through the net.

“This is a vital step in ensuring that we all live in an environment that supports our health.”

A recent poll for the Obesity Health Alliance of 2,085 people found that 74% supported the need for further Government action on obesity.

Almost eight out of 10 (78%) supported manufacturers reducing sugar in foods, while 74% backed not showing adverts for junk food before 9pm on TV and online.

Health Secretary Matt Hancock told the Health Select Committee on Tuesday: “Issues like obesity in particular clearly have an impact on how badly people are affected by coronavirus and we need to take action in order to make sure that people get more equal life chances across this country.”

Barbara Crowther, Children’s Food Campaign coordinator, said: “The Government already has many of the necessary ingredients for a new recipe to tackle obesity and build a healthier food environment for our children.

“However, launching an obesity plan without comprehensive 9pm watershed on TV and online advertising, and tightening marketing and promotional regulations, would be like trying to bake bread without yeast or leaven.

“It would simply fall flat.”