Controversial plans to raise the minimum age for buying alcohol from off-sales were backed today by delegates at the SNP conference.

The Scottish Government has put forward a series of proposals aimed at tackling Scotland's booze culture, including raising the age for buying alcohol in supermarkets and off-licences from 18 to 21.

The SNP's youth wing, Young Scots For Independence, put forward an amendment arguing that the proposal will "do little to tackle the real problem with Scotland's relationship with the bottle".

That was defeated by 131 votes to 190.

Delegates at the Perth conference also backed a motion welcoming the government's consultation on alcohol abuse.

The vote came after a heated debate, in which public health minister Shona Robison mounted a strong defence of the plans.

She told the conference: "We have a problem in Scotland without a doubt with our booze culture, it's holding us back as a nation, costing us £2.25 billion every single year."

Ms Robison said 40,000 hospital admissions each year were caused by alcohol misuse. "That is why as a Government, your Government, we have decided we need to make a priority of changing Scotland's booze culture.

"And of course any effective policy quite often has to be a radical policy," she went on.

"I make no apologies for bringing forward a radical set of proposals to try to change Scotland's relationship with alcohol."

The under 21 off-sales ban is being proposed after a series of pilots, with Ms Robison claiming these had seen calls about anti-social behaviour fall by more than 40%. "Those lessons cannot be ignored," she added.

Alison Thewliss, the national convener of Young Scots For Independence, argued that the move will demonise many young people.

She told the conference: "This party has an excellent record of standing up for the rights of young people, for being seen to look after the rights of young people.

"I don't believe that punishing many for the bad behaviour of a few people is the right way to go."

Ms Robison said: "It is not about demonising young people at all. The reality of the situation is that young people are the ones most likely to be on the receiving end of violence fuelled by alcohol on the streets of Scotland."

She stressed: "We as a Government are determined to get to grips with the booze culture in Scotland.

"The proposals we have brought forward are a basket of measures. Not one of them standing alone will solve the problem but taken together we believe that they will begin to change that relationship with alcohol to one where it can be a positive relationship rather than one which is based on misuse."