The UK government is to back the Scottish government when its minimum alcohol pricing legislation is challenged in the courts.
The law, aimed at tackling alcohol misuse by charging 50 pence per unit, is being challenged by the Scotch Whisky Association.
The European Commission has also raised concerns about its legality.
Advocate General, Lord Wallace of Tankerness, has said UK ministers will not "sit on the sidelines".
He is due to discuss the UK government's position on minimum pricing at a legal conference in Edinburgh later this week.
The coalition government has proposed a minimum price of 40p per unit of alcohol in England and Wales and plans to begin a consultation on the issue.
Minimum pricing legislation for Scotland was passed by MSPs at Holyrood earlier this year.
Five European Union countries have raised concerns that the proposal may infringe free trade rules.
The Scotch Whisky Association has sought a judicial review of the minimum pricing legislation in the Court of Session in Edinburgh.
Lord Wallace, a former leader of the Liberal Democrats, is due to speak at the University of Edinburgh on Tuesday.
In extracts from his speech, released ahead of the event, he said: "The proposal for England and Wales has the backing of the Royal College of Physicians and the Association of Chief Police Officers (Acpo).
"It could mean 50,000 fewer crimes and around 900 fewer alcohol-related deaths per year in England and Wales by the end of this decade."
He added: 'It would be open to the UK government to sit on the sidelines, and watch while the Scottish government seeks to fend off these challenges. But we will not do that.
"When the case is first heard in the Court of Session later this month, the UK government will be standing shoulder-to-shoulder with the Scottish government, seeking to support and complement the arguments that they present, and in particular ensure that the court has the benefit of the UK government's experience and expertise in EU law."
Research by Sheffield University has indicated that setting the minimum price at 50p would lead to 60 fewer deaths, 1,600 fewer hospital admissions and 3,500 fewer crimes in its first year.
The Scottish government has said it will fight any legal challenges to the legislation.
A spokesman added: "The Scottish government welcomes all support in our efforts to address Scotland's serious problems with alcohol misuse.
"We are confident that we can demonstrate, under European law, that the minimum pricing of alcohol is justified in Scotland on the basis of public health and social grounds.
"We believe that minimum pricing will save lives and reduce the harm caused by alcohol misuse and we also believe minimum unit pricing is the most effective pricing measure."