Government plans for a ban on multibuy alcohol promotions in England and Wales are far more draconian than the clampdown north of the border, it has emerged.

In Scotland, which introduced curbs on multibuys just over a year ago, retailers can charge different prices for different pack sizes - without sticking to the same unit price.

However, The Home Office has written to warn suppliers in England and Wales they will have no such leeway.

Theoretically, a retailer in Scotland can sell a four-pack of lager for £4 and a 12-pack for £11, but in England and Wales if a retailer stocked a four-pack, the price for an eight-pack of the same sized cans would have to be exactly double - and the price of a 12-pack three times the cost. In both jurisdictions. if cans are on sale individually, no multipack can cost less than the equivalent number of single cans.

The drinks industry warned of the complexity over pack sizes and pricing strategies this week.

“We’ve had confirmation from the Home Office that the restrictions will be much tougher than in Scotland,” said Aileen Keyes, director of public affairs at the wine and Spirits Trade Association. “This will add great complexity to the system - something that smaller producers may find difficult to cope with.”

A source at one major brewer said it had not realised the extent of the proposals until it was informed by The Grocer.

“Having flexibility over pack sizes and pricing is of massive importance,” he said. “This is a total interference in the market. There is also a major issue about how this impacts on price and pack sizes across the different countries.”

Keyes said suppliers were already looking at varying bottle sizes across different pack sizes, but that the new rules could penalise smaller producers with less flexible production.