UK business groups have said there is a need to maintain "stability" to avert a shock to the economy after the referendum result.
The CBI said "the urgent priority" was to reassure the markets and for the government and Bank of England "to shore up confidence and stability".
The British Chambers of Commerce said the immediate priority was market "stability and political clarity".
Bank of England governor Mark Carney promised support for financial markets.
He said the Bank is prepared to provide £250bn to support the markets, but added that "some market and economic volatility can be expected as this process unfolds".