Some of Wales’ biggest car dealers have expressed “concern and disappointment” that they remain unable to trade due to coronavirus.
Eighteen dealerships have written a joint letter to First Minister Mark Drakeford saying it is unfair they cannot operate but English rivals can.
They say “countless customers” will choose to buy there.
The Welsh Government said “non-essential” retail firms should prepare to reopen over the next three weeks.
Minister have said they would make a decision at the next Welsh Government review of the lockdown guidance – and that would depend on scientific and medical evidence.
The companies’ letter says Cardiff Bay’s refusal to allow dealerships to reopen for sales, in contrast to Westminster’s approach, had “exposed the whole sector in Wales to considerable harm”.
It says the retail motor industry in Wales has a combined turnover of more than £3bn and employs more than 20,000 people in sales departments alone.
“Consumers change their car on average once every four years. During the next three weeks countless customers will transact with our English counterparts, ending their relationships with local Welsh dealers,” the traders say.
“It should also be noted there is a built-up demand from the past nine weeks of lockdown eager to do business.
“We are confident the next three weeks’ loss will be much greater than any normal period. This revenue will never be recovered.”
Some dealers have continued to offer services and MoTs during lockdown.
Dealers said they were ready to reopen for sales, having invested an average £9,000 at each of their sites on social-distancing precautions, such as signs and personal protective equipment (PPE).
The letter goes on: “We applaud and support the efforts made to protect the health and wellbeing of everyone in Wales, however, we truly believe you have underestimated the professionalism and commitment in the retail motor trade.
“We are confident businesses can open in a safe and controlled manner exactly the same as our English counterparts.
“The retail sector as a whole is facing its biggest challenge in living memory, these recent actions have further increased the considerable pressure we already face and put Welsh jobs at risk.”
They further claim that, because the values of used cars depreciate, their aggregate value could fall by £6.3m in the next month for the 18 companies which have signed the letter.
Across the industry as a whole, they say that figure will be “much greater”.
Steve Hutchings, of the Hutchings Motor Group, said there was a disparity between the decisions of the devolved governments and the UK.
No reopening date for car showrooms has been announced in Wales or Scotland, but Northern Ireland’s will reopen next Monday.
“We as an industry have a huge amount of money invested in vehicles and they are depreciating,” said Mr Hutchings, whose company has sites in Bridgend, Pontypridd and Swansea.
Mr Hutchings said both the Scottish and Northern Ireland governments were looking to reopen car dealerships next Monday, which could leave Welsh dealers behind the rest of the UK for weeks.
“Just across the [Severn] bridge people will be able to buy.
“And absolutely there will be customers who will make the decision to travel across the bridge, purchase their cars.”
A Welsh Government spokesman said: “We have said that non-essential retail business which can comply with physical-distancing duty should prepare to reopen over the next three weeks, and we will take a decision at the next review.
“There is an ongoing risk to public health from coronavirus and any decision will depend on the scientific and medical evidence.
“We have delivered the most generous business support package in the UK, including £1.7bn of direct financial support for businesses of all sizes through our Economic Resilience Fund and grants targeted at those paying business rates in the retail, leisure and hospitality sectors.”