Checks and controls on GB food products entering Northern Ireland have been some of the biggest practical difficulties.

Under the Windsor Framework, UK public health and safety standards apply for all retail food and drink in the UK internal market.

That means GB traders who are sending food for sale in Northern Ireland face reduced checks and paperwork compared to the protocol.

The flipside of this is the introduction of the “Not for EU” labels on GB food products, to give a level of assurance to the EU that products will not wrongly enter its single market.

Mr Machin said the final phase of labelling would mean more than 1,000 Marks & Spencer products destined for Northern Ireland would need to have a “Not For EU” label.

Another 400 would need to go through additional checks in the so-called red lane at NI ports.

“Quite frankly it’s bureaucratic madness, confusing for customers, and completely unnecessary,” Mr Machin said.

In May the government announced an “agreement to agree” which will ultimately see all of the UK realigning with EU agrifood rules.