The boss of retail giant Next has warned over the threat of gridlock at ports and price hikes from increased tariffs if the UK crashes out of the European Union with no deal.
Chief executive Lord Simon Wolfson - a prominent Brexit supporter - has called on the Government to give businesses clarity on what measures could be taken to relax customs procedures and border controls.
He said the likelihood of queues and delays at UK and EU ports posed the biggest risk to Next from a no-deal Brexit.
“If the ports seize up it will be a problem,” he said.
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"In fashion you're always selling out of the best-sellers. The ports that will have the biggest problems will be the ones having more EU goods, so basically Dover."
In an unusually detailed document outlining the group's no-deal contingency plans, Next also cautioned that another sharp fall in the value of the pound and increased tariffs also posed a threat.
Next said in the "unlikely event" that free-trade agreements were not put in place, it could send the cost of imported goods soaring by up to around £20 million, which could push up prices by around 0.4%.
"There are significant challenges involved in preparing for a no-deal outcome and we would not want to understate the work we are doing to prepare for this eventuality,” the retailer said.
"However, we do not believe that the direct risks of a no-deal Brexit pose a material threat to the ongoing operations and profitability of Next's business here in the UK or to our £190 million turnover business in the EU."
Local residents in Dover have also expressed fears about gridlock.
Representatives from the Port of Dover, which is the second busiest port in England, have already warned of serious traffic congestion in the town and surrounding areas unless the government can negotiate a deal involving frictionless trade.
The Port of Dover's head of policy, Richard Christian, told the Guardian that in the event of a hard Brexit, "regular gridlock" could occur in Kent, causing disruption to freight traffic on ferries and Eurotunnel services.
Speaking to talkRADIO's Alex Dibble, Councillor Nigel Collor of Dover District Council described the impact of heavy traffic:
"We had a situation here at the end of July, which is the big school holiday getaway, and it wasn't freight traffic then, it was tourist traffic. In other words cars, coaches and caravans, and they just couldn't get through. The Port couldn't cope with them quick enough. There was no problem at the Port, it was just purely the volume.
"Bus services were suspended or cancelled because they couldn't get through, taxis gave up coming to this part of the town where we are now, if the life boat had been called out the crew would have had great difficulty getting to the station, and above all, carers couldn't get to the people that need their help."