Demand for new cars fell by 39.5% last month compared with January 2020, new figures show.
Just 90,249 new registrations were recorded as showrooms across the country remained shut, the Society of Motor Manufacturers and Traders (SMMT) said.
It was the automotive industry’s weakest start to a year since 1970.
SMMT chief executive Mike Hawes said: “Following a £20.4 billion loss of revenue last year, the auto industry faces a difficult start to 2021.
“The necessary lockdown will challenge society, the economy and our industry’s ability to move quickly towards our ambitious environmental goals.
“Lifting the shutters will secure jobs, stimulate the essential demand that supports our manufacturing and will enable us to forge ahead on the road to zero.
“Every day that showrooms can safely open will matter, especially with the critical month of March looming.”
— SMMT (@SMMT) February 4, 2021
Demand for diesel cars was down 62.1% last month, with petrol models declining by 50.6%.
Sales of battery electric and plug-in hybrid cars continued to buck the overall trend, with rises across the UK of 54.4% and 28.0% respectively.
RAC data insight spokesman Rod Dennis described the boost in sales of alternatively fuelled cars as “extremely encouraging”.
He went on: “It remains to be seen what the rest of 2021 will bring when it comes to drivers’ appetite to opt for diesels, and whether the numbers sold will ever return to pre-Covid levels.”