The Government's sugar tax plans have come under renewed attack, amid suggestions ministers are preparing to publish draft legislation.

Coca-Cola, Pepsi and Red Bull are among the drinks which could be hit by the levy, announced by then chancellor George Osborne as part of his final Budget in March.

Celebrity chef Jamie Oliver celebrated the surprise move, set to be brought in from April 2018 to give manufacturers time to drive down the sugar content of their drinks.

Mr Osborne predicted the charge - officially known as the "soft drinks industry levy" - will raise £520 million for school sport funding.

A lower rate will apply to companies if they make a drink with five grams of sugar per 100 millilitres and a higher rate for drinks with more than 8g per 100ml.

The Treasury has previously said the levy is designed to make producers reduce the added sugar in their products and reduce portion sizes, which in turn officials hope will play a role in reducing obesity levels among children and adults.

MPs have warned of loopholes in the original plans, including that sugar-heavy milkshakes and pre-mixed alcohol drinks would not be subjected to the levy.

The Treasury is due to make a written statement to Parliament today, Monday, related to draft clauses for Finance Bill 2017.

Amid suggestions the sugar tax draft legislation is set to be published on Monday, British Soft Drinks Association director-general Gavin Partington said: "Evidence worldwide does not suggest that taxes of this sort have any impact on levels of obesity.

"However, we will review the legislation when published and will continue to work with Treasury officials during the process of implementation."

The Taxpayers' Alliance labelled the sugar tax an "ill-thought-out reaction" to pressure from the public health lobby.

Chief executive John O'Connell said: "Lasting change will happen via a long-term cultural shift, not by burdening the poorest families with a higher cost of living."