Billionaire investor George Soros has warned a Brexit could see sterling fall by 20% against the greenback, more than when he profited from betting against the currency ahead of Black Wednesday in 1992.
Writing in The Guardian, Soros (pictured) said the pound would fall by at least 15% if the UK votes to leave the single European market, and potentially more than 20% to below $1.15 against the dollar.
He said voters are underestimating the importance of the vote and the immediate effects it will have on the UK economy.
"Sterling is almost certain to fall steeply and quickly if leave wins the referendum," Soros wrote.
"I would expect this devaluation to be bigger and also more disruptive than the 15% devaluation that occurred in September 1992, when I was fortunate enough to make a substantial profit for my hedge fund investors at the expense of the Bank of England and the British government."
Soros famously made $1bn profit from 'Black Wednesday' on 16 September 1992, with a wager that the UK would be forced to devalue the pound and withdraw it from the European Exchange Rate Mechanism.
Now worth $24bn, he said a devaluation in sterling following a Brexit would be less benign than in 1992 because the Bank of England will be unable to cut interest rates, currently at record lows.
He also noted Britain's current account deficit is currently larger than 1992 and 2008, and more dependant on foreign capital than ever before, which would be reduced in the event of a departure from the EU.
He said "Brexit would make some people very rich, but most voters considerably poorer".
"Today, there are speculative forces in the markets much bigger and more powerful. And they will be eager to exploit any miscalculation by the British government or British voters," he said.
According to a Bloomberg survey of economists, the pound will either sink to the lowest level in more than three decades or climb towards the highest this year the day after the referendum.
In the event of a 'leave' vote, participants expect the pound to fall to between $1.25 and $1.40, while a 'remain' vote could see the currency rise beyond $1.50.