Difference between soft Brexit and no deal worth £15bn – analysis

NIESR warns if no agreement reached, chancellor's spending power will be much reduced

The impact of Brexit on next week's budget has been spelled out by one of Britain's leading economic forecasters, with the difference between a soft and no-deal outcome worth around 15bn over the next five years for Philip Hammond.

According to the National Institute of Economic and Social Research (NIESR), the chancellor could increase spending on public services above and beyond the 20bn promised for the NHS - but only if Britain retains the closest possible relationship with the EU following its departure.

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