Shops will start to run out stock within weeks if chaos at the borders does not ease, according to supply chain experts.

Six out of 10 supply chain managers said they are running into problems with new customs controls and Covid-19 checks that are delaying goods coming into the UK from Europe, research by the Chartered Institute of Procurement & Supply (CIPS) found. Delays ran for several days in about a third of cases.

With stockpiles that were built up ahead of Christmas and in case Britain crashed out of the EU without a deal now running down, the institute warned that shelves could soon start to empty.

It forecast a “significant impact” on consumers in the next few weeks, with almost a quarter of supply chain experts saying they would run low on stock should the situation at the border continue.

John Glen, CIPS economist, said: “Worryingly, delays at the border will get worse before they get better.

“Traffic through the border since January 1 has been low compared to historical levels, but with December stockpiles depleting it won’t be long before trade traffic increases and more pressure is placed on these new border processes.

“As the transportation of goods grows, so will the queues, and businesses may be forced to limit or halt production to cope with any potential stock shortages.”

He added that a “confluence of customs’ inability to handle the new paperwork, ramping up in volumes, increasing complexity at ports because of Covid, and freight carriers being unwilling to come to the UK for fear of being held up add extra costs”.

And unless there is urgent action to free up trade flows the issue will only intensify.

“This is not a ‘bump in the road’, as some are saying, that we can cross our fingers and hope for the best it works out – that bump is in danger of turning into a chasm,” Mr Glen said.

“There is unlikely to be a ramp up in customs capacity in the short term to deal with it and freight brokers we are talking to say they are working flat out to service existing customers and cannot take on new customers.”

CIPS found that issues with complex customs procedures and coronavirus tests were being exacerbated by reduced staff numbers to check documents because of social distancing measures to prevent the spread of the virus.

Extra time taken for customs officials to examine the new paperwork is the main cause of freight delays, blamed in just over a quarter of all cases. Covid checks were responsible for just over a tenth of them.

While food supplies are likely to be the first area where shortages occur, if manufacturers cannot get hold of materials they need, problems could soon spread, Mr Glen said.

Goods going the other way into the EU are almost as badly affected, with 45pc of the 185 CIPS members surveyed saying they are experiencing delays, 28pc of them saying these are lasting several days.

The study also revealed that 17pc of business are importing or exporting far less as a result of stockpiling, but said they will have no option but to increase trade across the border as supplies run low, ramping up traffic at customs and potentially worsening the situation.

Almost a fifth are braced for goods to be delayed as this occurs, with many expecting higher costs for transportation and dealing with red tape.

The warnings were echoed by Logistics UK, which said the delays were a consequence of the lack of time that supply chains had to prepare, and the lateness of the Brexit trade deal.

“With so little time available between the end of the transition period and the start of new trading arrangements with the EU, there was no time available to run a live trial of the new processes required before January,” said Elizabeth de Jong, policy director at the trade body.

“As a result, the logistics sector has been working through the issues in real time, and businesses have had to learn on the job, with traders, transport companies, government agencies – in Great Britain, Northern Ireland and in the EU – all finding out whether their planning and understanding was sufficient.”

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