Before the start of post-Brexit trade talks in Brussels last week, David Frost, Britain’s chief negotiator, prepared by tucking into a full English breakfast. But from the end of the Brexit transition next January, ordering Mr Frost’s patriotic fry-up in the EU’s capital might become much more difficult.

Exporting unfrozen processed meat products such as sausages to the bloc’s single market will require an export health certificate — completely new paperwork which currently does not exist for that sort of food. Meanwhile, dairy products such as milk, yoghurt and eggs will need a vet to sign off their provenance, something which could cost between £200-£900 per product.

Boris Johnson’s election victory in December not only removed business concerns over a Jeremy Corbyn-led Labour government but lifted hopes he would be a pro-business prime minister.

But relations are already turning sour over his hardline stance on Brexit. Rather than delivering a bonfire of Brussels regulations, business leaders are reeling from a succession of government announcements that suggest trading will become increasingly difficult and costly without a new comprehensive trade deal.

“I am feeling punch drunk at the moment,” said Nick Allen, head of the British Meat Processors Association, who warned of the impact on consumers if the UK and EU fail to agree a zero tariffs, zero quotas trade deal by the end of the year.

“Our members are international companies who can [currently] move products back and forward without worries.”

With the UK stepping up preparations for a coronavirus epidemic and stock markets falling, Rishi Sunak’s first Budget on Wednesday may have more pressing issues to deal with. However, business lobby groups want to see Mr Sunak provide some comfort on the biggest long-term issue facing the British economy.

He is not alone, with products from pharmaceuticals and chemicals to clothes and components at risk of being tangled in red tape over customs and product testing.

Dominic Goudie, head of international trade at the Food and Drink Federation, said: “It’s clear that the needs of business are not always at the forefront of government’s considerations.”

Richard Harrow, head of the British Frozen Food Federation and former managing director of Freiberger UK, the pizza maker, who is worried about the impact of post-Brexit immigration and tariffs policies on his sector, said: “It feels like Boris has come out saying that I have a big majority so don’t need to consult business any longer.”

Within days of the UK formally leaving the EU on January 31, Michael Gove, the cabinet office minister overseeing EU trade talks, started warning businesses about “friction” and “inevitable” checks at the border — a position reinforced by a government spokesperson on Monday.

“The UK will leave the EU’s customs area and the EU’s single market,” the spokesperson said. “We will not seek alignment with the EU in any way. This means that there will be new processes that exporters and importers will have to comply with, whether we reach an agreement or not.”

“We are waving the white flag,” said Mr Harrow.

If you’ve got short-life food, then any material delay at the border will take life out of that product, which will be expensive. If you’ve got very highly tuned supply chains like the automotive industry, again, there will be issues

The British Retail Consortium (BRC) counts up to nine documents that would be needed to sell a British product to an EU country. Under any sort of deal, exports and imports will need a certificate of origin, transit certificates, customs valuation documents and, if exporting to Northern Ireland, destination paperwork to ensure goods are not then moved to the EU.

Without a comprehensive trade agreement, there will need to be other pieces of paper: VAT and excise documents, freight certificates, health and veterinary documents, exit and entry summary declarations, and safety and security permits.

The costs are potentially high. Customs declarations alone cost between £15 to £56 for each product category in a truck — with almost 7,000 freight movements every day in Dover alone, and mixed load lorries commonplace, this means a “significant amount of money per truck”, the BRC said.

HMRC estimates the reintroduction of import and export declarations could add £7.5bn of annual costs for companies, while the British Chambers of Commerce said that customs declarations could jump almost sixfold to about 300m a year, also citing official estimates.

This will require an extra 50,000 border agents to handle the paperwork, according to the government — although Pauline Bastidon, head of policy at the Freight Transport Association, said its members thought that this “underestimates the needs, if anything”, given it does not include the need for safety and security declarations.

The government counters that it will “continue to pursue policies that make the UK the best place in the world to do business and improve our economy”. Officials insist that the level of disruption will ultimately depend on the outcome of the trade talks with Brussels and that the government remains committed to achieving a zero tariff and zero quota trade deal with the EU.

Nevertheless, John Allan, chairman of Tesco and president of the CBI, said businesses were “still pretty anxious about what the future relationship with Europe is going to be [and] how comprehensive the eventual trade is”.

Manufacturers warn that without a deal that keeps friction to a minimum, much of the cost on importing goods from the bloc will be passed to British consumers. William Bain, trade policy lead at the BRC, said that “any increase in cost in a low-margin industry is ultimately going to be faced by the consumer. And it’s not simply about cost, it’s also about availability, choice and quality.”

Any delay on the border caused by the need to show paperwork will mean lost time on the shelves. “If you’ve got short-life food, then any material delay at the border will take life out of that product, which will be expensive,” said Mr Allan. “If you’ve got very highly tuned supply chains like the automotive industry, again, there will be issues.”

Trade bodies are now lobbying the government with checklists of requirements to ensure smooth flow of goods next year — but some still wonder whether they will be prioritised in the highly politicised trade talks.

Despite its hardline stance, the government insisted it was still listening. “We will continue to talk to businesses over the next nine months to ensure they are ready for 2021, as we negotiate new trading relationships with the EU and around the world,” a spokesperson said.

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