PUBS should offer smaller measures of wine to help tackle ­excessive drinking ­according to the Scottish Government.

A campaign to urge more bars and restaurants to sell wine by 125ml glasses has been launched and backed by the pub trade.

Many bars offer only two sizes, medium and large, in 175 or 250ml measures, with the larger equal to one third of a bottle - comparable to three units of alcohol.

Michael Matheson, Public Health Minister, said too many bars ignore the small measure which does not promote responsible drinking.

He said: "All too often we see only medium and large size measures of wine available behind the bar and this can mean people end up drinking more than they realise.

"A large glass of wine can contain over three units of alcohol, which is in excess of a woman's daily recommended intake of alcohol and equivalent to a man's recommended daily intake.

"Clearly it is important that people have the ability to choose a smaller measure if they wish and by offering the 125ml measure, businesses are giving their customers the opportunity to drink responsibly."

The campaign includes pubs making available a 125ml measure for wine; and including the option and the price on menus.

It calls for promotional material to encourage ­people to choose the smaller measure and making sure all staff are aware the measure is available.

Bodies representing publicans backed the campaign and said their members are committed to reducing harmful drinking.

Paul Waterson, chief ­executive of the Scottish ­Licensed Trade Association (SLTA), said: "Our customers have told us that they welcome increased choice and that the offer of small, medium or large glasses of wine in our premises will make them think more about the amount of alcohol they are consuming."

Patrick Browne, chief executive of the Scottish Beer and Pub Association, said: "As an association we are fully supportive of the initiative and will commend it to our member companies, their pubs, and the wider licensed trade."

Arguments have even been made for scrapping the 250ml serving on grounds of not only health, but price and quality.

It has been stated from some within the pub trade that to sell wine in larger amounts and to keep the price still roughly the equivalent to a pint or a spirit and mixer, then only cheaper wines are possible to ensure a profit.

The health argument is customers are unaware ­exactly how much they are consuming but if a wine drinker is drinking two or three drinks with someone having the same number of pints of beer, they are consuming much more alcohol.

A 250ml glass of 14% abv wine has around 35ml of pure alcohol compared to 21ml in a pint of 3.8 abv beer or lager.

It is also argued to restrict choice and quality with only three drinks per bottle, but trying to keep the price at around or below the £4 mark, then better quality wines are ruled out.