Investors sent the FTSE 100 slumping to its worst one-day fall in four months as mounting concern about the global economy and worries about a potential Brexit sent fund managers scrambling for safe-havens.

London’s blue-chip index tumbled 116.13 points to 6,115.76, a 1.9pc slide that was its heaviest since February 11 and came as equities around the world were gripped by an aggressive sell-off. The pound also slumped 1.5pc against the dollar - its sharpest fall in four months - after a new poll gave the Leave campaign a 10-point leave in the EU referendum.

In France the CAC 40 lost 2.2pc, Germany’s DAX was down 2.5pc and in the US the S&P 500 had fallen by 0.7pc by the time the London market was closed.

Bonds were the beneficiary as investors sought shelter from the stock market turmoil, with yields on British, German and Japanese government debt all touching fresh record lows. Demand for government debt such as US Treasuries has also been driven by the European Central Bank’s negative interest rate policy, which has pushed investors looking for yield into bonds that offer better returns.

A cocktail of concerns unnerved equity investors today.

Fund managers are becoming increasingly fearful about the health of the world economy and are eyeing a series of events that have the potential to destabilise markets.