Yes campaigners launch new push

The move comes at the end of a bad week for independence campaigners as the Scottish Social Attitudes Survey revealed a historic low level of support for a separate Scottish state.

Speaking in Glasgow on Friday, Yes Scotland chief executive Blair Jenkins said: "We are keen to move the debate from the 'how' to the 'why' of independence.

"We want people to start thinking about what kind of country they want, what kind of country Scotland could be and to think about why being independent could be the best way to achieve our aspirations and goals."

But the annual Scottish Social Attitudes Survey published on Wednesday showed that support for independence had fallen back to 23 per cent in 2012 from 32 per cent the year before.

Between 1999 and 2006 support for independence averaged 30 per cent but since 2007 - after the SNP came into office in Holyrood - it has tended to be lower.

Rachel Ormston, director of the authoritative survey, said there were lessons for both sides of the independence debate.

"The Yes campaign still needs to convince a much wider section of the public that independence will bring real benefits, especially for Scotland's economy.

"But, while independence does not appear to be the favoured option of most Scots at present, unionists need to recognise there is a substantial gap between the public's perceptions of Holyrood's current powers and their preference for it to be responsible for most of Scotland's domestic affairs."