Vehicles made and approved in the UK could no longer be sold in the EU if Great Britain crashes without a deal, a shock government document admits.
EU "type-approval" would no longer be granted to prove that the vehicles "comply with safety and environmental standards", warned.
It was issued only two days after the boss of Jaguar Land Rover had attacked the Brexit strategy of Theresa May and warned that those tens of thousands of jobs were being compromised.
Manufacturers must request approval from a body in an EU Member State – if such an agreement can be concluded.
The document says that if there is no Brexit deal, the government would act unilaterally to ensure that cars made by the EU in this country can still be purchased by recognizing approvals.
But it recognizes that Brussels may no longer be prepared to consider the British Vehicle Certification Agency (VCA) as a suitable body for sale in the EU.
"In a no-deal scenario, type approvals issued in the UK would no longer be valid for sales or registrations on the EU market," says the document.
"This means that involved manufacturers must ensure that they have the correct type approval for each market."
And it adds: "SCC would continue to act as a technical service for testing UK type approvals, but it can no longer be recognized as a technical service by EU type-approval authorities."
This week, the president-director of Jaguar Land Rover – at a conference where the Prime Minister was present – warned of the "horrific" consequences of a tough Brexit, which cost the company £ 1.2 billion a year.
Ralf Speth said: "Brexit will take place on March 29, next year and I do not know at the moment whether one of our production facilities in the United Kingdom can operate at 30," he warned.
Gareth Thomas MP, a Labor Member of Parliament and in favor of the anti-Brexit Best for Britain group, as "another unnecessary blow to the country's auto industry".
"Failure to deal with no-deal could mean that the future of British car exports to the EU could remain in balance and damage an industry filled with thousands of highly qualified jobs," he warned.
"This scenario without a deal can not be considered seriously as an option if we know how much is at stake."
However, the transport department said it was "incorrect" to say that UK-produced cars could not be sold in the EU after a no-deal Brexit, and that manufacturers could insist on an EU approval authority. ask.
"The decisive factor is whether they obtained EU type approval in the UK or an EU Member State, not where they were manufactured," according to a spokeswoman.
The situation is another example of how the "no deal" preparations of the government actually mean trying to enter into a series of separate micro-agreements with the EU, to do enormous damage.
Dominic Raab, the Brexit Secretary, has written to the EU to propose what he calls "no deal deals" when the need arises – but Brussels had previously rejected such an approach.
The Independent has launched the # Finalalay campaign to require voters to vote for the latest Brexit deal.