A 20% tax on sugary drinks would be a "useful first step" towards the long-term goal of taxing a wide range of products in the fight to reduce obesity, doctors' leaders have said.
With a third of the UK population projected to be obese by 2030, the British Medical Association (BMA) said imposing the tax could reduce the number of obese British citizens by around 180,000.
The BMA is the latest body to call for a tax on sugar - a move that was ruled out by Health Secretary Jeremy Hunt last year.
Its report, Food For Thought, warns that poor diet costs the NHS around £6bn a year, meaning it has a greater impact on its budget than alcohol consumption, smoking or physical inactivity.
It suggests that imposing a 20% tax on all non-alcoholic water based beverages with added sugar, including sugar-sweetened soft drinks, energy drinks, fruit drinks, sports drinks and fruit-juice concentrates, could subsidise the sale of fruit and vegetables.
It also criticises the Government for placing too much emphasis on industry involvement in developing food and nutrition policy in the UK through the use of public-private partnerships.
It said the approach of partnership working has also provided a platform for companies to promote and enhance their own brands, meaning that commercial companies are the main beneficiaries.
The report's author, Professor Sheila Hollins, said: "While sugar-sweetened drinks are very high in calories they are of limited nutritional value and when people in the UK are already consuming far too much sugar, we are increasingly concerned about how they contribute towards conditions like diabetes.
"We know from experiences in other countries that taxation on unhealthy food and drinks can improve health outcomes, and the strongest evidence of effectiveness is for a tax on sugar-sweetened beverages.
"If a tax of at least 20% is introduced, it could reduce the prevalence of obesity in the UK by around 180,000 people.
"We know that the majority of the UK population, particularly low income households, are not consuming enough fruit and vegetables, so financial measures should also be considered to subsidise their price, which has risen by 30% since 2008.
"This is an important way to help redress the imbalance highlighted previously between the cost of healthy and unhealthy products, which particularly impacts on individuals and families affected by food poverty."