Scottish Licensing Act, arguing that the new laws, which are due to come into force in Scotland on Tuesday, do not make it clear whether offering promotions on alcohol will still be legal.

The act bans "irresponsible promotions", which it defines as being any that "encourage a person to buy or consume a larger measure of alcohol than the person had otherwise intended to buy".

Interpretation is being left to Scotland's 32 regional licensing boards, potentially creating a postcode lottery.

At one point this week, the Edinburgh licensing board indicated it was to outlaw multibuy offers, including three-for-£10 offers on wine. Following protests from the industry, it backed down, saying it would not actively enforce the law for the off-trade and would only investigate if it received a complaint.

Industry bodies are calling for more clarity. "It speaks volumes that days before the law comes into force retailers are still unsure of what the laws are," said Gavin Partington of the Wine & Spirit Trade Association. "Retailers need clarity to end this chaos and confusion. We are calling on the Scottish Government to spell out clearly how the legislation should be applied, so there's no scope for different implementation by different licensing boards."

Katie Mackie of the Scottish Grocers' Federation said having different rules in different parts of Scotland would cause a problem for retailers, many of whom needed to plan promotions for the entire country.