In his first major public ­pronouncement on the new ­alcohol laws since they were introduced last week, justice secretary Kenny MacAskill told industry experts: “If a buy-one-get-one-free is wrong in the pub, it’s also wrong in the supermarket”. Mr MacAskill also squared up to the whisky industry by rubbishing their claims that his proposals for minimum pricing would have an impact on exports.

So far, government guidelines have excluded “off-sales” such as major chains and supermarkets, and concentrated on pubs and clubs. However, Mr MacAskill’s comments mean that licensing boards can now target two-for-one deals, excessive discounts and bulk buy savings across Scotland. Even meal deals which include wine could be affected if it was thought that shoppers were being encouraged to buy a larger quantity than otherwise.

His comments on supermarkets come despite claims by trade lobbyists that such a move would be illegal. At an Alcohol Focus conference at Aviemore, Mr MacAskill said: “Trade bodies have asked us to rule out the possibility of boards using the Act to ban multi-buy promotions in supermarkets. I am not going to do that. The 2005 Act does extend promotions bans to off-sales.

“Notwithstanding the guidance issued by the previous administration, if boards take the view that a certain promotion is contrary to the Act, then they should ban it.”

Mr MacAskill said the government was convinced that discounted promotions in bulk were wrong.

“We will not want to stand in the way of any boards that feel able to apply such a ban at a local level,” he said.

The justice secretary admitted this would lead to difficulties for national chains as they will have to contend with different policies in different areas, but said “it is each premises that is licensed and each premises that must comply with whatever arrangements are in place locally.”

Mr MacAskill’s comments will infuriate the alcohol industry and large chains, which had been looking for a commitment that there would be no restrictions on off-sales until the new Alcohol Bill was passed. But the move has been welcomed by campaigners, who claim local authorities should now monitor the sales techniques of all premises within their areas.

Mr MacAskill urged the authorities to “use the Act to its full effect”, warning against “an ultra-cautious approach”.

He dismissed the view that more education is needed instead and claimed that “minimum pricing is moving from being a radical idea to a mainstream view”, with recent support for proposals from the Welsh Assembly.

He said much of the industry opposition to minimum pricing had been channelled through the Scotch Whisky Association (SWA), who are concerned that some foreign governments will use action in Scotland to justify unfair practices in their own country.

But he said the association’s rationale was fundamentally flawed because minimum pricing was being pursued as a public health policy and not market protection, and that all products were being treated fairly by linking the minimum price to the ABV, not to the type of drink.

He added: “The SWA should not underestimate their ability to successfully challenge any unfair practices in any country. They’ve been doing that for years.”

“We accept that some parts of the alcohol industry remain opposed to minimum pricing. Some think we should pretty much tolerate Scotland’s alcohol problem or plough on with more and more education -- an approach that has a place but that on its own has been shown to be insufficient, and would remain insufficient.

“If the alcohol industry can come up with an alternative approach that is deliverable, fair, and which would reduce consumption and harm to the same extent as minimum pricing, then we want to hear about it.”

Ministers have given the green light to banning drinks promotions in supermarkets and ­off-licences