(Bloomberg) -- U.K. car sales got off to the slowest start in half a century as dealerships were among the businesses forced to shut their doors to contain the resurgent coronavirus.

Registrations plunged 40% in January to 90,249 cars, the lowest for the month since 1970, according to the Society of Motor Manufacturers and Traders. Battery-electric models remained a rare bright spot with sales growing 54%, though they still represent just 6.9% of the market.

The U.K.’s auto lobby group cut its 2021 sales forecast by 5% to less than 1.9 million cars and called for showrooms to be opened as soon as Covid-19 cases are suppressed to protect employment. More than 10,000 jobs were cut across the sector last year and post-Brexit trade complications are weighing on the industry’s recovery prospects.

“Every day that showrooms can safely open will matter,” Mike Hawes, SMMT’s chief executive officer, said in a statement.

Prime Minister Boris Johnson has come under mounting pressure to ease restrictions, including from lockdown skeptics in his own party who fear shutting businesses will have lasting effects on the economy. While officials said this week the U.K. has passed the peak of its latest wave of cases, infections are still widespread.

Car production in the U.K. fell to the lowest since 1984 last year. While the trade agreement Britain reached with the European Union largely spared the industry from tariffs, it’s brought about more onerous customs procedures and requires companies to make components locally to avoid levies.

Honda Motor Co. will close a plant in Swindon, England, later this year, and Vauxhall maker Stellantis NV is deciding in the coming weeks whether to invest in its factories making combustion-engine cars and vans.

(Updates with final data in the second paragraph.)

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