(Decanter) - Opponents of minimum pricing of alcohol have criticised Prime Minister David Cameron’s forthcoming speech on the 'scandal' of alcohol abuse in the UK.On a visit to a hospital in north-east England, Mr Cameron is to call for the drinks industry to do more to tackle a problem which costs the National Health Service £2.7bn a year. A ban on the sale of alcohol below cost price - less than the tax paid on it - is set to be introduced in England and Wales from 6 April, but ministers are expected to push for a higher minimum price for drink.