Three in four UK manufacturers are facing export delays due to Brexit, Britain's manufacturing lobby has said.
Make UK, the industry group for the manufacturing sector, said 74% of its members had faced delays in the past three months and many were still struggling to get goods through ports.
Almost a third of members are experiencing delays of up to two weeks and half said the delays were pushing up costs. One in five said they'd lost business as a result of the delays.
"Government needs to move smooth out difficulties at UK ports so that shipments can easily be delivered," said Stephen Phipson, chief executive of Make UK.
"We are encouraged that government is already working to train more high quality customs officials and to give more assistance with customs paperwork, but this needs to be driven forward at speed to give the quickest possible assistance to British companies already struggling to get back to normal as trade recovers from the COVID pandemic."
Dutch bank ING this week said UK exports to Europe "fell sharply in January."
"French data shows a 20% decline in imports from the UK in January as trade frictions were introduced, while imports from the rest of the world increased," ING economist James Smith said. "Data from the German and Italian statistics agencies suggest similarly dramatic falls."
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The UK government has said declining trade with the EU is a result of COVID-19 and stockpiling, not Brexit.
"The jury's out on how much was solely down to Brexit-related disruption," Smith said.
Friday's monthly UK GDP data would give "the first, concrete sense of the damage from the switch to new EU-UK trade terms at the start of the year," he said.
Make UK represents 5,000 UK manufacturers and Phipson urged the government to work with the industry and counterparts in the EU to find solutions to problems at the border.
“Government should look to quickly get back around the table with our EU partners to find a way to mitigate against ongoing delays at the border and iron out different interpretations of the rules for movement of goods in separate member states," he said.
The plea came as relations between the two sides sours. The UK has unilaterally moved to give businesses in Northern Ireland more time to adapt to post-Brexit trading rules, which the EU say is in violation of the Brexit agreement. The EU is pursuing legal action over the breach, the Guardian reported on Wednesday.