The UK car industry suffered its worst new car sales since 1996 in June.
According to preliminary figures from the Society of Motor Manufacturers and Traders (SMMT), new car registrations in the UK fell by around 24% last month compared to June 2021.
The trade body said a global shortage of components such as semiconductors continued to hinder manufacturers' ability to meet demand.
Drivers must wait more than 12 months to receive certain models.
Only about 800,000 new cars were sold in the first half of this year.
That was a 12% drop from the same period in 2021 and was the industry's second-lowest January-June performance since 1992.
Jim Holder, editorial director of the magazine and website What Car?, said car buyers were being hit by a series of problems.
New car orders are delayed, while rising energy bills drive up manufacturing costs, which in turn push up prices.
"The result is longer wait times for cars and higher purchase costs," he warned.
Separate data from green car consultancy New AutoMotive showed that 16% of new car registrations in June were pure electric vehicles, up from 11% in the same month last year.
The company's co-founder, Ben Nelmes, said last month that electric vehicles "continue to grow, while total new car registrations are down by a quarter", thus "defying gravity".
He warned that rising petrol and diesel prices were "pushing consumers towards electric vehicles", but that car supply was "not keeping up with demand".
"We've heard that lead times for electric vehicles are now between 40 weeks and a year. The supply of electric vehicles is the biggest obstacle to clean road transport in the UK," he added.
The UK government is planning to pass the Zero Emission Vehicle (ZEV) Directive, which will require manufacturers to sell a certain percentage of these cars and vans from 2024.
Mr Nelmes urged ministers to ensure this level was "above" the proposed 22% to "attract more electric vehicles into the UK".
The UK has committed to achieving net zero carbon emissions by 2050.
To achieve this, the sale of new petrol and diesel cars and vans will be banned from 2030.
