The boss of home improvements chain B&Q has warned that investment would be put on pause in Scotland if there is a vote for independence.
Ian Cheshire, whose multinational firm Kingfisher owns the DIY outlets, said there are too many uncertainties surrounding currency and Scotland's place in the EU.
The prospect of a Yes vote in September also puts on hold plans for a further 23 Screwfix shops, he said.
Mr Cheshire, speaking at his newest B&Q warehouse in Port Glasgow, Inverclyde, insisted he will not pull out if Scots decide to leave the union.
But he said such a move "would put a pause on everything".
"If we have differences on VAT, currency, it just puts everything into hibernation as we try to figure out what it will mean. At the end of that we have to consider what is the trading environment," he stated.
"Because Scotland is such an important part of B&Q, there's no way we're going to let it go, but it would be more complicated, probably more costly and less likely to attract investment, given we could invest in 11 other countries around the world," he added.
B&Q employs more than 2,600 people in Scotland and around 20,000 across the UK. Screwfix, which Kingfisher also owns, has 27 shops in Scotland employing just under 400 people.
Although the company operates across borders, the impact of change would cause him problems.
The company's UK-wide IT system would have to change and thousands of products may have to be repriced in B&Q and Screwfix, he said.
He insisted his warnings are from a purely business angle, and that it would be wrong to say Scotland would not be capable of being independent.
Earlier this year, British Chancellor George Osborne and other UK party leaders ruled out the Scottish Government's preferred option of creating a sterling union across the border after independence.
The Scottish Government's White Paper on independence also sets out the case for smooth transition to EU membership within the 18 months between a Yes vote and formal independence in 2016.