Theresa May could axe customs union membership to access £17bn worth of trade deals according to a Boris-backed Brexit campaign
Theresa May can secure trade agreements worth twice the amount offered by the European Union if she takes the UK out of the customs union, according to leading Brexiteers.
Research from Change Britain, a campaign group backed by foreign secretary Boris Johnson, found 14 countries have expressed interest in a trade pact.
And the economies of those nations total £16.8bn, almost double the amount of equivalent countries which have a trade deal with the EU.
Read More: One of the three Brexiteers hints the UK will quit the EU customs union
However, such deals would be prevented if May opts to remain within the customs union, which requires members to apply a common external tariff on trade with other nations.
Former CBI boss and Change Britain supporter Lord Digby Jones said: "We can strike trade deals with the rising economies of the 21st century, many of whom have already signalled their intentions to begin negotiations.
"This will allow British business to export to millions more customers and create thousands of new jobs throughout the UK. We should grasp this opportunity with both hands."
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The figure come as the EU finally inks a trade deal with Canada after more than seven years of talks.
Canadian Prime Minister Justin Trudeau and EU commission president Donald Tusk signed the deal today, with the latter issuing an impassioned defence of free trade.