Boris Johnson is not hiring Tony Abbott for his trade expertise | Larry Elliott

The ex-Australian PM is a political evangelist for free trade who has got three big trade deals over the line

It is often said, in a phrase once attributed to Benjamin Disraeli, that there are three categories of mistruths: lies, damned lies and statistics. By the same token there are three types of geeks: geeks, super-geeks and trade negotiators.

Trade negotiators know the difference between the bound and applied tariff on imports of cars into Brazil. They know the quota for frozen lamb that can imported into the EU from New Zealand. They know their way around all 22,500 pages of commitments made by different countries at the end of the Uruguay round of trade talks in 1993. These people are experts and, despite what the health secretary, Matt Hancock, has said, Tony Abbott is not one of them.

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