Scotland will become the first place in the UK to introduce minimum drink pricing, after MSPs passed new laws.

The SNP government will set the price of alcohol at 50p per unit, to tackle Scotland's historic alcohol abuse problems.

Under the plans, the ­cheapest bottle of wine would be £4.69 and a four-pack of lager would cost at least £3.52.

The move won broad political backing, although Labour refused to support the legislation at the Scottish Parliament.

The Alcohol Minimum Pricing Bill , which aims to help tackle drink-fuelled violence and associated health problems, cleared its final parliamentary hurdle when MSPs backed it by 86 votes to one, with 32 abstentions.

Scottish government justice minister Roseanna Cunningham voted against the legislation by mistake.

Scottish Health Secretary Nicola Sturgeon said that, as drink had become cheaper, alcohol-related hospital admissions had quadrupled and half of prisoners said they were drunk when they committed offences.

Describing the vote as a "historic moment", she told parliament: "Tackling alcohol misuse is one of the most important public health challenges that we face in Scotland."

'Windfall' concern

Labour said minimum pricing could generate profits of more than £125m for alcohol retailers, but the party failed in a bid to change the legislation to allow the government to claw back the "windfall".

Jackie Baillie, Labour's health spokeswoman, agreed there was a link between price and alcohol consumption, but added: "Labour believes there will be significant unintended consequences if the windfall remains with supermarkets that can actually undermine the very purpose of the bill itself."

A study into a 50p minimum alcohol price by Sheffield University said the policy would see a 5.5% cut in drinking - with harmful drinkers' consumption falling by more than 10%, compared with a 2.5% fall for moderate drinkers.

That would mean harmful drinkers having to spend more than £120 extra a year to keep up their habit, with an £8 increase for moderate drinkers, according to the research.

The Conservatives and Liberal Democrats, who previously opposed minimum pricing, backed the move, along with Labour MSP Malcolm Chisholm, a former health minister.

Deputy Tory leader Jackson Carlaw said: "I hope very much that it will work. I fear it cannot achieve all that some have hoped for it, but I believe it will make a contribution and that is what parliament must hope in passing the legislation."

Willie Rennie, the Lib Dem leader, who said he had always supported minimum pricing but had to stay "relatively quiet" about it in the past, added: "The battle has just begun to deal with this problem and we need to make sure that it's absolutely effective to deal with the alcohol blight that we have in society."

Minimum pricing, which made its second passage through parliament after it was defeated in 2010 when the SNP was a minority government, will be ditched after six years if the policy fails, under a "sunset clause" in the legislation.

Scottish ministers said minimum pricing had won wide support across the medical profession, police and parts of the drinks and licensed trade industry.

But some groups, including the Scotch Whisky Association, have questioned the legality of the policy, under EU law.

On her voting mishap, Ms Cunningham later wrote on Twitter: "Ooooops! Discovered that I accidentally voted the wrong way on the minimum pricing bill :-( #roseannafail *shuffles feet in embarrassment*."

MSPs previously passed legislation banning "irresponsible" drink promotions at off licences, which also paved the way for the introduction, in future, of a "social responsibility fee" on retailers who sell alcohol.

The Scottish government also brought forward a public health levy on large retailers which sell tobacco and alcohol.

A 40p minimum alcohol price is planned for England and Wales.