UK car production suffered its slowest September since 1995 as the pandemic continued to batter demand, industry figures show.
Just 114,732 vehicles rolled off production lines last month, said the Society of Motor Manufacturers and Traders (SMMT).
That is down 5% on September last year.
The SMMT called the drop worrying, as the UK and EU had still not agreed a free trade deal with just 63 days to go until the end of the transition period.
"The fact that both sides are back around the table is a relief but we need negotiators to agree a deal urgently, one that prioritises automotive, enhances innovation and supports the industry in addressing the global threat of climate change," said SMMT boss Mike Hawes.
"With production already strained, the additional blow of 'no deal' would be devastating for the sector, its workers and their families."
Exports declined 9.7% in September to 87,533 units as exports to China, the EU and the US all fell.
UK and European carmakers warned last month that a no-deal Brexit could put a £100bn dent in the region's car industry in the next five years, adding to heavy losses already caused by Covid-19.
A letter signed by 23 trade groups across Europe urged the government to make a deal rather than default to World Trade Organization (WTO) rules.
A deal is seen as crucial because of how interconnected the industry is, with parts passing many borders as a car is assembled.
Talks over a post-Brexit trade deal resumed in London last week after negotiators returned to the table following a standoff.
Key areas of disagreement include fishing rights, post-Brexit competition rules and how any deal would be enforced.
While the UK has left the EU, it has continued to follow EU trading rules during its post-Brexit transition period.
This 11-month period is due to end in December, and the UK has ruled out seeking an extension.