New car sales last month were down around 13% on the pre-pandemic April average, preliminary figures show.
Around 141,000 new cars were registered in the UK in April, the Society of Motor Manufacturers and Traders (SMMT) said.
That is approximately a 30-fold increase on the same month in 2020, when the country was in a full coronavirus lockdown.
But it is about 13% lower than the April average between 2010 and 2019.
Final figures will be released by the SMMT at 9am.
Jim Holder, editorial director of magazine and website What Car?, said the coming months will be “critical” to the automotive industry’s recovery from the pandemic.
He predicted that “demand will remain strong”, but stressed the importance of showrooms remaining open for the remainder of the year.
Another lockdown would be “potentially ruinous for many operators”, he said.
Mr Holder also warned that a global shortage of microchips has created a car production backlog, forcing some manufacturers to suspend operations.
“What this means for consumers is potentially longer waiting times on vehicles they’ve already ordered or are looking to order, and diminishing stock to choose from,” Mr Holder said.
“The production setbacks will likely take months to solve, meaning the delays could be significant. That means more bad news for new car makers.”
The SMMT recently raised its forecast of the number of registrations this year to 1.86 million, up from the figure of 1.83 million it issued in February.
It said this is because “the economic backdrop has improved noticeably over the recent weeks on the back of successful vaccine rollout”.
An annual total of 1.86 million would represent a 14% increase on last year.