Latest: UK stats watchdog stands firm in Brexit row with Boris Johnson

Latest: The head of the UK statistics watchdog has refused to back down in the public spat with the British Foreign Secretary over his Brexit claims.

Update 7.40pm: The head of the UK statistics watchdog has refused to back down in the public spat with the British Foreign Secretary over his Brexit claims.

Boris Johnson accused David Norgrove of a "complete misrepresentation" of his views and called on him to withdraw the criticism.