Brexit Britain giving up a three-course meal for a bag of crisps

Britain leaving the European customs union to strike free trade deals with countries outside the EU is “giving up a three-course meal for the promise of a packet of crisps”, a top ex-civil servant has said.

Sir Martin Donnelly, who left his role as permanent secretary to Liam Fox’s Department of International Trade last year, said 60% of UK trade was either with the EU or the countries it had trade agreements with.

Any divergence from Brussels rules would deal a blow to British services which would not be compensated for through deals with nations like the US, he added.

He told BBC Radio 4’s Today programme: “You’re giving up a three-course meal, which is the depth and intensity of our trade relationships across the European Union and partners now, for the promise of a packet of crisps in the future if we manage to do trade deals outside the European Union which aren’t going to compensate for what we’re giving up.

“You just have to look at the arithmetic – it doesn’t add up I’m afraid.”

Meanwhile Boris Johnson dismissed concerns that leaving the customs union could lead to a hard Irish border by comparing travel between the Republic and Northern Ireland to driving from Camden to Islington in London.

The foreign secretary said: “We think that we can have very efficient facilitation systems to make sure that there’s no need for a hard border, excessive checks at the frontier between Northern Ireland and the Republic.

“There’s no border between Islington or Camden and Westminster, there’s no border between Camden and Westminster, but when I was mayor of London we anaesthetically and invisibly took hundreds of millions of pounds from the accounts of people travelling between those two boroughs [through the congestion charge] without any need for border checks whatever.

“It’s a very relevant comparison because there’s all sorts of scope for pre-booking, electronic checks, all sorts of things that you can do to obviate the need for a hard border to allow us to come out of the customs union, take back control of our trade policy and do trade deals.”