Nearly two out of three businesses in Alex Salmond's own back yard in the north-east say they do not know enough about the implications of independence to decide how to cast their vote.

A survey for Aberdeen & Grampian Chamber of Commerce (AGCC) last month found only 35% of firms in Aberdeen and Aberdeenshire, where the First Minister's Aberdeenshire East constituency is located, think they know enough to take a view. Some 61% say they do not.

Across Scotland, 37% say they do not know enough.

The status of an independent Scotland in Europe is the issue on which most want elaboration.

The findings are revealed in a survey circulated by AGCC in conjunction with Stirling University economics Professor David Bell and co-funded by the Economic and Social Research Council (ESRC), published today.

The survey results are drawn from a sample of more than 800 firms from the Scottish Chambers of Commerce network, with 159 (20%) from Aberdeen or Aberdeenshire.

The respondents represented the main sectors of the north-east economy, from sole traders to companies with more than 500 employees.

James Bream, research and policy director at Aberdeen & Grampian Chamber of Commerce, said: "We are not surprised by the findings that companies are unsure what impact independence would have on their business, and it is definitely a cause for concern."