Nestlé chairman Peter Brabeck-Letmathe has said that the company could be forced to re-evaluate the extent of its presence in the UK if Britain decided to leave the European Union.
In an interview during the World Economic Forum in Davos, Brabeck-Letmathe said the company was committed to its business in the UK but that he could not envisage a separation from its biggest trading partner being in the country's interest.
Nestlé, whose brands include Nespresso, Kit-Kat, Nescafé, Smarties and Yorkie employs approximately 8,000 people in the UK and accounts for exports worth roughly £400m.
"From a purely economic point of view, I can't see that the withdrawal of the UK [from the EU] would be favourable for any UK industries," said Brabeck-Letmathe.
"It would isolate the UK economically. Every company would be forced to re-evaluate the implications of investing in the UK. It would no doubt have an impact on its ability to supply European markets."
The warning, reported by Mark Kleinman, city editor of Sky News, comes ahead of a likely referendum on Britain's EU membership in 2017, and echoes the views of many of the multinational business leaders gathered in Davos.
Meanwhile, Paul Polman, the chief executive of Unilever and chief of consumer goods group, says the European Union is good for business and the UK economy. The UK would be better off staying inside the European Union "than kicking against the table" and voting to leave, he said.
He added that Unilever could review its UK investment if Britain left the EU, according to Jennifer Rankin of the Guardian.
Polman said he supported EU reform but added that the debate was simplistic. "We tend to forget all the good things that the common market has brought, also to Britain, and take that for granted and then only focus on the things that need to be changed and portraying that as bad," he added.
Polman was speaking as Unilever surprised the City with better than expected results for 2013. The company reported net profit of €5.3bn (£4.4bn) for 2013, up 9% on last year, sending its share price up 2.5%.
Prime Minister David Cameron told Sky News on Thursday that he did not believe the Government's stance on EU membership was jeopardising inward investment, saying that companies had been voting with their feet. He said: "The argument I make with these business leaders is that the best thing for Britain would be to secure our place within a reformed European Union.
"Simply saying ‘let's hope this issue goes away, let's hope that Europe sorts itself out', without doing anything, won't work. We need to get in there, change Europe, make it work better, make it more competitive, make it more flexible - help make Britain more comfortable with its membership, have that referendum and then settle this issue."