Rob Hollyman, the director of Youngs Transportation and Logistics, said: “Any strike action would be yet another nail in the coffin of what is left of the haulage industry. It is just awful.”

It is unclear what effect any strike action, which would be likely to take effect in the run-up to Christmas, would have on the number of lorry drivers prevented from working as a consequence.

The majority can carry on driving lorries while a licence application is being processed, but a significant number – thought to be several thousand – would be hit by any further backlog.

The PCS has been calling for a reduction in the number of staff working on site at the DVLA. Industrial action began in February and it is reported that 58 days have been lost to strikes in that time.

Mark Serwotka, the union’s general secretary, said: “We want a deal that has Covid safety measures at its heart, appropriate reward and recognition for staff working throughout the pandemic and a workplace recovery plan, agreed with the union. If our members vote once again for strike action, we will support them every step of the way.”

A DVLA spokesman said it was too soon to say what effect, if any, a strike would have on the existing backlog and stressed that most drivers can continue working while licences are being processed.

But in a statement the DVLA said: “The safety of our staff is paramount. We have worked with public health bodies throughout the pandemic who have confirmed a high level of compliance and have no concerns.

“It is extremely disappointing that PCS continues to pursue unnecessary industrial action which will hold millions of motorists across the country to ransom.”