Britain’s car industry risks losing out even if there is a post-Brexit trade deal with the EU, according to documents seen by the BBC.
Car parts from Japan and Turkey used in the UK will not be treated as British, so some exports may see higher tariffs.
In a letter, Britain’s chief Brexit negotiator says the UK has failed so far to get the car parts deal it wants, and “obviously cannot insist on it”.
Having enough parts sourced within the UK and EU is key to a free trade deal.
In a letter to the car industry, seen by the BBC, chief negotiator Lord Frost says one of their key priorities - that parts and components from Japan and Turkey count as British in any deal - has been rejected by the European Commission.
This risks some UK automotive production attracting taxes on trade, known as tariffs, when exported to the EU, even if there is a “zero tariff” trade deal struck with the EU.
A separate draft legal text, also obtained by the BBC, lists the UK’s request for manufacturing of electric cars, batteries, and bicycles to be treated leniently, and count as British, even if the majority of components come from elsewhere.
The letter says: “I am sorry to say that so far they [EU negotiators] have neither been willing to discuss these nor share any proposed text with us”.
Both documents refer to the need, even in a deal, for UK manufacturers to prove that UK-exported goods are actually British-made, with a specified threshold of British parts, expected to be around a half.
Under the terms of an anticipated deal with the EU, any components from EU countries can count as British - something known as “cumulation”.
But the letter reveals the requirement for that to be extended to other partners of the UK and EU, in particular Japan and Turkey, is being refused.
Much UK manufacturing is below the required threshold, although the reverse is not the case for the European Union. The problem is particularly acute for electric vehicles where an even larger proportion of the value of the car is contained in the battery.
“The commission has made clear that it will not agree third-country cumulation in any circumstances, which we regret, but obviously cannot insist upon,” says Lord Frost’s letter, written on 7 September.
Senior figures in the car industry expressed the view that the government could have chosen to insist on a deal that did contain such measures. But discussions on such subjects have been stalled by the impasse over fishing rights and subsidy powers.
The original Brexit deal negotiated by former PM Theresa May contained a route to minimise checks on what are known as “rules of origin”.
That option was removed as part of the revision to the withdrawal agreement a year ago. But Lord Frost points out that the UK and EU27 car industries have jointly asked for such arrangements, including special consideration for electric vehicle exports.