The Commons' Health Select Committee has said there is "compelling evidence" a tax would reduce sugar consumption and help in the battle against child obesity in England.
The Committee's report, which acknowledges that no single measure will solve the problem, also calls for a crackdown on marketing and advertising, as well as a drive to force industry to reduce sugar in food and drink.
Treating obesity and its consequences currently costs the NHS £5.1 billion every year.
Around a fifth of children start primary school overweight or obese, rising to a third by the time they leave. Fizzy drinks are the single biggest source of sugar for 11 to 18-year-olds
The report from MPs comes just a month after a review by Public Health England, which backed similar measures. TV chef Jamie Oliver has also called for the introduction of a tax on fizzy drinks.
But food industry representatives have questioned whether a new tax is the most effective way of reducing consumption, or whether it is fair on consumers.
The report draws on evidence from Mexico, which introduced a 10% tax on sugar-sweetened drinks and saw a corresponding 6% reduction in consumption.
The report is an attempt to influence government policy, which is due to be finalised next year with the publication of a child obesity strategy for England. Until now the government has resisted calls for a so-called 'sugar tax'.
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