UNCERTAINTY about Scottish independence poses a "tremendous challenge" for Scotland's business leaders, according to a study.

But the work by Edinburgh University, involving interviews with 60 medium and large employers, showed that the independence debate had thus far only influenced the business decisions of five of them; for the other 55 it was "business as usual".

Recent reports suggested that major Scottish companies like Standard Life, RBS and Lloyds have begun contingency planning on the possibility of a Yes vote in September's referendum.

The university study found contingency planning "varied markedly". Of the 60 firms, 26 were in discussions about it, nine were monitoring risks, 20 had drawn up analysis, nine were restructuring, six were relying on continuity plans and two were deferring investment.

It explained across all sectors "business leaders identified uncertainty as the main challenge they faced" with the key risks in the event of independence being the "currency, new regulations, taxes, particularly income taxes, recruitment and retention of employees, and EU membership".

In energy, engineering and manufacturing, electronics and technology, financial services and life sciences, 23 business leaders said they had yet to identify any obvious opportunities from independence while a further seven said the opportunities would be marginal. Of the 30 business leaders able to cite opportunities, only in eight cases were they able to cite potential opportunities specific to their business.

Overall, six of the 60 business leaders said, at present, the opportunities presented by independence outweighed the risks, while 54 said the risks outweighed the opportunities. The study noted that the "perceived opportunities" post-independence were government funding or subsidies, income tax decreases, liberal immigration policies, and corporation tax cuts. Its author, Brad Mackay, Professor of Strategic Management at the University's Business School, said: "For many large businesses in Scotland, the potential risks presented by the independence referendum appear hard but the perceived opportunities seem much softer."

Better Together seized on the study with Labour's Ian Murray saying: "The message from Scotland's employers is that independence would cost jobs."