Scottish retailers are alarmed by the lack of detail in the Alcohol Bill, which they say could give the Scottish government sweeping powers and have a severe impact on small stores.

Proposals include a minimum price per unit of alcohol, a ban on 'irresponsible' promotions, a restriction on marketing materials and giving government the power to impose a social responsibility fee on retailers.

Licensing boards would also be instructed to consider raising the off-sales purchase age to 21.

Introducing the Bill, health secretary Nicola Sturgeon said it was "a once in a generation chance to turn around Scotland's drink problems".

But Scottish Grocers' Federation (SGF) chief executive John Drummond said: "The lack of detail in the Bill will prohibit the Scottish Parliament from properly scrutinising measures which will have a huge impact on the trade and consumers."

On promotions, he said: "It is particularly harsh of the government to penalise those who drink responsibly at a time when there is increased pressure on household budgets."

Association of Convenience Stores chief executive James Lowman added: "Banning alcohol promotions will undermine local shops' ability to compete with larger retailers, who sell alcohol at the lowest prices. Promotion restrictions are arguably more damaging for retailers than minimum prices."

The proposed age rise would "establish ridiculous anomalies", Drummond said. "This would allow licensing boards to decide the locality of a ban which could result in responsible retailers being caught in the net."

The Bill now enters the committee stage before its first reading in parliament.