Brexit is ranked by chief financial officers of leading UK firms as the most significant risk facing their companies, according to a new survey.

Some 83% of CFOs questioned for the Deloitte European survey rated the level of economic uncertainty facing their business as 'high' - an increase of 11% since the previous quarter. Just 1% classed the current level of uncertainty as 'low'.

The report found that the June 23 referendum on UK membership of the EU had 'eclipsed' long-standing anxieties about emerging markets and eurozone growth as a key concern for European businesses.

Business Stronger in Europe deputy director Lucy Thomas said: 'UK businesses are clear that leaving the EU now poses the biggest threat to Britain's economic security.

'The uncertainty already being felt ahead of the referendum is nothing compared to the economic havoc caused by leaving the EU single market, which would leave Britain worse off by an average of £4300 per household each year.'

'This is yet more evidence that staying in Europe is the best way to secure jobs and financial security for British families.'