Guto Harri and Boris Johnson
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Boris Johnson's heart not in Brexit, ex-aide Guto Harri says

Boris Johnson made a "spectacular miscalculation" in backing the Brexit cause as his heart was not in it, an ex-aide has said.

The former London mayor announced on Thursday he would not be taking part in the contest to succeed David Cameron, who resigned as Tory leader and prime minister after the referendum vote in favour of the UK leaving the European Union.

Guto Harri, a former BBC Wales journalist who was Mr Johnson's director of communications during his time as mayor, said the nation as a whole was paying a "heavy price" for his miscalculation.

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