"Post-Brexit, some people are calling for the UK to remain a member of the customs union that comprises the EU member states and Turkey. There are several reasons why this is a bad idea."

 

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"One of the strongest arguments for leaving the EU was restoring the ability of the UK to set its own trade policy. This would give us the ability to reduce import duties both to lower the prices of goods for consumers and as part of free trade agreements (“FTAs”) with other countries who would reduce tariffs on our exports in return."

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"The common external tariff (which sets out the duties and quotas that apply to imports into the customs union) imposes duties on products that the UK does not produce so has no domestic interests to protect. Often these form stumbling blocks in the EU’s negotiations with third countries, for example the FTA negotiations with Japan stalled on discussions around products like wine and tinned tomatoes, delaying a deal that would have reduced tariffs on auto parts and opened up services access in Japan."

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“Viewed in this light, the entire Brexit process should be regarded as part of a wide-ranging exercise–government departments must work together so that we can exit the EU in such a fashion that the high-level vision of growth, prosperity and hope can remain intact in our negotiations with other countries."

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Read: Why we must leave the Customs Union