hey are called non-tariff barriers and we are seeing them built up between the UK and the EU. Technically, there is free trade without tariffs but, in practice, physical trade is being impeded and trade in services (not covered by the agreement) is being blocked by excessive bureaucracy.
Thus there have been the hold-ups at Calais and Dover, Scottish fish unable to be exported to Europe, the famous sandwich incident when Dutch customs officials confiscated a Polish driver’s lunch, and problems of deliveries to Northern Ireland.
There have also been financial blockages, less obvious but equally disruptive. Some trading has gone from London to European capitals, but it seems quite a lot of business has gone to New York, because the EU recognises US regulations as “equivalent” to its own, whereas it has not yet agreed that with London.