Boris Johnson has compared the border between Northern Ireland and the Republic of Ireland to the border between Camden and Westminster in London.
The foreign secretary said on Tuesday it would be possible to avoid a hard border on the island of Ireland after Brexit thanks to technology.
“There is no border between Islington, Camden and Westminster. There is no border between Camden and Westminster,” he told BBC Radio 4′s today programme.
“But when I was mayor of London we anesthetically and invisibly took hundreds of millions of pounds from the accounts of people traveling between those two boroughs without any need for border checks.”
Drivers in London’s congestion charge zone do not face physical checks.
Challenged over how the relationship between two parts of London was the same as between the UK and the EU after Brexit, Johnson added: “I think it’s a relevant comparison.
“There’s all sorts of scope for pre-booking, electronic checks, all sorts of things you can do to obviate the need for a hard border to allow us to come out of the customs union.”
Sadiq Khan, London’s Labour mayor, ridiculed his predecessor’s argument.
“It is breathtakingly idiotic even by Boris Johnson’s standards to conflate the complexities and sensitivities of the border between Northern Ireland and the Republic post-Brexit with the border between Camden and Westminster,” he said.
Labour MPs, including those representing London constituencies, were also unimpressed.
The European Union is set this week to publish its draft text of what the UK’s final Brexit deal will look like.
The document is expected to conclude that Northern Ireland would remain inside the customs union in order to avoid a hard border on the island of Ireland.
The British government has rejected such an approach as it would effectively split the UK and place a border in the Irish sea. “We don’t think that is the right way forward,” Johnson said.
Jeremy Corbyn has increased the pressure on Theresa May when he confirmed yesterday Labour will back a “new and comprehensive” UK-EU customs union to ensure tariff-free trade.
Corbyn’s initiative has set the scene for possible defeat for the prime minister in an upcoming Commons vote on the Trade Bill.
International Trade Secretary Liam Fox will today claim remaining in a customs union with the EU after Brexit would be “a complete sell-out of Britain’s national interests”.
In a warning to any Tories tempted to join Labour in voting through an amendment requiring the Government to seek a post-Brexit customs union, Fox will say that the arrangement would constrain the UK from taking advantage of future trade opportunities