Political uncertainty over Britain's place in Europe and the Scottish referendum have become "critical factors" in company investment decisions, according to a business leader.
Sir Mike Rake, president of the CBI, says that, while the economic recovery is increasing, political issues are climbing up the "risk register" for businesses.
He will tell the CBI's annual dinner in London: "Over the next 18 months, we face various challenges. Starting with European elections, then the Scottish referendum, the general election and then a possible EU referendum in 2017.
He said: "As our economic situation has stabilised and now looks more promising, the focus of business concern has shifted towards these issues.
"The uncertainty they engender is climbing up businesses' risk registers, becoming a factor in investment decisions."
Sir Mike will say that the most pressing issue for businesses is the Scottish referendum, adding that while the decision on independence is for the Scottish people to take, the CBI will continue to raise economic questions on the issue.
He added: "The decision on independence is, of course, for the Scottish people. But the effects of the decision will be felt by others, including businesses - not just in Scotland but in Wales, Northern Ireland and England.
"The CBI has the right and duty to ask the difficult questions about issues which affect our members' interests and this country's economic future.
"Ultimately, because of the range of unknown and unforeseen consequences of independence, it is difficult to see how independence would be better for investment and for jobs. The case has not been made that an independent Scotland would be better for our economy."
Business Secretary Vince Cable said: "It's right to highlight that leaving the UK could present sizeable risks to Scottish businesses. As recovery takes hold, now is the time to exploit joint strengths and opportunities, not weaken them.
"The UK Government is setting out a clear case that Scottish firms benefit from our shared currency, free and unhindered trade links, a strong and diverse labour market and UK-wide research and investment opportunities."
Edinburgh South Labour MP and shadow business minister Ian Murray said: " Our UK single market is vital for Scottish employers and sustains so many jobs here. Scottish businesses have access to a market of over 60 million people across the whole of the UK, rather than just five million people in Scotland.
"Why would we want to put up barriers between Scottish firms and their customers elsewhere in the UK? If we leave the UK, it would create uncertainty for Scottish firms and cost jobs here."
He added: " As part of the UK we can have the best of both worlds - a strong Scottish Parliament, with the guarantee of more powers for Scotland, and the strength, security and stability of being part of the larger UK. Only separation puts that at risk and we should not be taking risks with the jobs and livelihoods of Scots."
But a spokeswoman for the pro-independence Business for Scotland group said: "T he CBI's reputation has already been permanently damaged by its No campaign which has led to the withdrawal of membership by more than 20 Scottish organisations.
"As CBI membership declines, that in Business for Scotland is increasing by the day and now stands at just under 2,000 people. This organisation's growth is clear testament to the fact that more and more businesses here see the opportunities that independence offers them.
"They see that Scotland's economy will thrive in the hands of a Scottish Government that understands its needs."