How the next US president could make or break Brexit

The US is Britain ’s single largest trade partner, with imports and exports between the two countries reaching 304bn in the last 12 months .

A comprehensive free trade agreement with Washington was held out as one of the main prizes to be gained from the UK leaving the EU .

The prospects for liberalisation of UK - US trade are at best in stasis and, at worst, on the cusp of a major reverse.

A victory for Kamala Harris unlikely to be quite so consequential for direct US - UK trade.

But there are big opportunities for UK export growth to the US in both services and goods.

Experts argue that in contrast to the heady days of Thatcher and Reagan , there has been a more fundamental shift in the utility of the special relationship.

MI6 and CIA warned that the world order is “under threat in a way we haven’t seen since Cold War’s Cold War .

Security co-operation between London and Washington is almost certainly one area where disruption to status quo can be ruled out regardless of who emerges victorious from Tuesday 's election.

The same cannot be said, however, for ensuring that Britain and its European allies have the military hardware and manpower to adequately defend themselves.