UK-EU trade faces hurdles post-Brexit

New formalities are now required for British goods entering the EU

For months officials pledged the flow of goods and services between Britain and the EU would remain smooth after Brexit, but a series of hiccups and delays shows the days of frictionless trade might well be over.

New customs and administrative formalities are now required for British goods entering the European Union -- except, in theory, between Spain and the British territory of Gibraltar, and between Northern Ireland (Britain) and Ireland (EU).

While the majority of shipments have continued, others have become targets of the more stringent checks. On Friday, six freight loads bound for EU-member Ireland were turned away at the port of Holyhead in Wales for not having the correct paperwork, Stena Line ferries said.

Even in Northern Ireland, reports have emerged of shortages at Sainsbury´s grocery stores because of new Export Health Certificates required for food entering from Britain.

A small number of our products are temporarily unavailable for our customers in Northern Ireland while border arrangements are confirmed, Sainsbury´s said in a statement.

And in France this week, many fresh food shelves stood empty at Marks and Spencer stores in Paris after they were unable to secure popular sandwiches, pork pies and other British fare made in Britain.

Due to new UK/EU import legislation, we´re sorry some of your favourites might be missing. We´re working hard to get them back soon, signs said in both French and English.

European retailers have reported difficulties in selling to British buyers because of new rules on the application of value-added sales taxes (VAT). As of January 1, Britain requires a customs declaration on all packages going between the United Kingdom and the EU, and merchandise is subject to VAT.

To make things more complicated: For products sent to Britain valued at less than 135 pounds (150 euros, $185), it´s the seller who pays the tax. But if the value exceeds 135 pounds, VAT is charged to the recipient -- forcing EU businesses to scramble to revamp their policies.