On course for record output by 2020, Britain's automotive industry has been one of the country's great success stories in recent years, employing over 800,000 people in the sector to produce for the likes of Jaguar Land Rover, Nissan and Mini.
"The greatest threat to that progress is Brexit," said Mike Hawes, chief executive of the Society of Motor Manufacturers and Traders (SMMT).
"To leave in 2019 without a deal would put the industry in peril, defaulting to WTO tariffs and customs barriers would damage our industry permanently," he said, referring to the two-year talks which are under way between London and Brussels.
The sector has consistently warned that the imposition of tariffs and a loss of access to its biggest export market following Britain's departure from its EU could hurt investment and threaten the viability of the huge car plants.
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