Boris Johnson's Brexit deal 'would cost UK economy £70bn'

Plan would shave up to 4% from size of economy by the end of 2020s, says thinktank

Boris Johnson's Brexit deal is expected to cost the UK economy as much as 70bn over the next decade compared with remaining in the EU, according to one of the country's leading economic thinktanks.

In a warning in the run-up to a snap election, the National Institute of Economic and Social Research (NIESR) said the prime minister's plan would shave up to 4% from the size of the economy by the end of the 2020s, equivalent to about 1,100 per person per year, compared with a situation where Britain remained in the EU.

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