Bank of England governor Mark Carney has announced £250 billion of financial support for the economy as the markets reacted to the vote to leave the European Union.

In a bid to restore calm Mr Carney insisted that the UK economy was “well prepared” for the financial shock.

Banks had been stress tested for much more catastrophic scenarios he insisted.

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But he said that "some market and economic volatility can be expected" in the wake of the Brexit vote.

More than £100bn was wiped off the value of the UK’s biggest companies within minutes of the markets opening at 8am.

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Banks bore the brunt with Royal Bank of Scotland down 28 per cent, Barclays down 27 per cent and Lloyds 24 per cent.

The pound also crashed 8 per cent against the dollar, falling from 1.50 US dollars to 1.36.

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