The FTSE 100 was set to fall by a near-record amount at the open with futures indicating an 8.2 per cent plunge - more than 500 points - in the first minutes of trading, after the UK voted to leave the EU.
Last night the index closed at 6,338.1 points, up 1.23 per cent as traders quelled their fears over the outcome of the EU referendum. However, experts have previously predicted that shares could lose as much as 10 per cent over the next few months.
European traders may have had a preview of what Friday morning will be like from Asia, where huge selloffs hit markets.
The Nikkei 225 was down by more than eight per cent and trading was suspended for 10 minutes after circuit breakers kicked in.
Meanwhile, the pound experienced its biggest-ever fall against the dollar, dropping 9.7 per cent to $1.3433, and falling 5.9 per cent against the euro to $1.2299.
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