Only around 40 percent of the parts that go into the average British-built car are made domestically and some trade deals require between 50 and 55 percent local content, a factor which could be crucial for post-Brexit trade.
After Prime Minister Theresa May said Britain would leave the single market and potentially the customs union when it exits the European Union, there has been greater focus on the manufacturing supply chain.
British-built cars can currently count EU-made content but that could change depending on the terms of the Brexit deal, with Nissan recently calling for a supplier fund to help boost the number of locally-made components.
Yet the required investment in businesses and skills could take years to bear fruit, and the volumes involved may not justify the spending.
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