British car output fell in 2019 at the fastest rate since the recession due to weak exports and diesel demand. To protect the sector, an industry body called for a post-Brexit trade deal.
Meanwhile, investment soared to 1.1 billion pounds (1.5 billion) due to Jaguar Land Rover building electric vehicles in Britain.
Production fell for the third consecutive time at an annual 14.2%, to 1.3 million cars in 2019, partly caused by extended factory closing due to Brexit disruption, Society of Motor Manufacturers and Traders said.
The global sector was hit by weaker sales in major markets like China, as well as the need to invest billions in electric cars.
Exports from Britain declined following weaker demands from China and Japan, which was at 26.4% and 17.7%, respectively.
The sector is now seeking to bind closer ties with the European Union, its largest market, in the hopes of avoiding tariffs and custom barriers post-Brexit.
Britain is set to leave EU on Jan. 31, followed by a transition period until the end of the year. Afterwards, politicians will have to negotiate future partnership past 2020.
While output is estimated to fall only slightly in 2020, some investments are due, affecting future turnout.
UK Prime Minister Boris Johnson plans to take advantage of opportunity post-Brexit to better trade with the US, where 19% or car exports are sent. However, the sector is keen on maintaining a smooth trade with the EU.