Unless working assumption is that the 'friction' can be managed 'away from' the border, which is a distinct possibility.
Will keep reading...
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The UK will agree an operational legal text for a #backstop for NI... but will negotiate a future partnership that ensures that this will not have to be used.
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In keeping with Joint Report of 8th Dec.17
Esp cos UKGov slides on Economic P'ship (24 May bit.ly/2N8McQE) implied UK wants deeper cooperation than others enjoy but minus the necessary institutional structures