Adults who buy cigarettes for underage smokers could be setting them up for a life of health problems and financial costs, a charity chief has warned.

Alastair MacKinnon, the chief executive of the children's health education charity Fast Forward, is calling on adults to stop giving tobacco to youngsters.

On average 36 young people in Scotland take up smoking every day, according to campaigners at Ash Scotland.

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While some adults will purchase cigarettes for children under 18 in the belief they are "doing them a favour", the charity has launched a new campaign against proxy purchasing - where an adult buys age restricted items for underage youngsters.

And to help Mr MacKinnon has pledged to champion Scotland's Charter for a Tobacco-free Generation - six principles laid down by Ash towards a smoke free nation.

More than 180 organisations are already signed up to the Charter, pledging to help do what they can to eradicate smoking in Scotland.

Ash Scotland has also launched its #notafavour campaign, aiming to highlight the problems caused by proxy purchasing.

Mr MacKinnon said: "Some adults think that they're doing young people a favour when they buy them tobacco - particularly if it happened for them when they were at school. But it's not a victimless crime.

"We know from talking to teachers that in schools where smoking rates are high in the local community, cigarettes are sold to younger children by teen smokers in order to maintain their own smoking.

"Tobacco given to a young friend or relative finds its way to new child smokers and that is what keeps the tobacco industry in business.

"Adults willing to buy tobacco for young people are really just carrying out the work of Big Tobacco. They're leading young people into addiction, long-term health problems and huge financial cost. It has to stop."

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Ash Scotland chief executive Sheila Duffy added: "The tobacco industry uses every trick in the book to snare new young people into becoming smokers, with the result that 36 children start smoking every day in Scotland. We mustn't do their job for them.

"Two thirds of adult smokers want to quit, and the vast majority started young. Smoking is an incredibly harmful addiction and still Scotland's leading cause of death.

"The vast majority of adults know it's wrong to buy tobacco for young people and don't do it. We're committed to getting the message out."