Several large-scale smuggling incidents show that EU concerns over the operation of the Northern Ireland Protocol are not theoretical, Brussels has said.

Seizure of counterfeit high-value electrical products last year, fitted with the European Union-type plugs, show the need for robust processes at Northern Ireland ports, an EU official said.

The official said there was evidence criminals were trying to use the Irish Sea crossing to get prohibited products into the EU single market.

Drugs and weapons have also been seized, the official said.

“There is smuggling going on, for sure,” they added.

The EU official said the ongoing failure by the UK to provide real-time data on trade movements in a useable format meant the EU was unclear “how big the problem is” in relation to smuggling.

However, the official said seizures made by UK Border Force, with the involvement of EU personnel on the ground, have indicated it was a significant issue.

“In March 2021, there was a seizure of undervalued and counterfeit high-value electronic products such as smartphones sent in parcels, plugs were EU type,” said the official.

“Between April and May 2021 and in October 2021 there were seizures of smartphones including counterfeit ones, tobacco, cigarettes, weapons, drugs and medicines hidden in parcels.

“In December 2021, in the context of control on postal deposits, there were seizures of heroin, cocaine, cannabis, 177,000 prescription medicine tablets, 24 kilos of tobacco, nearly 17,000 cigarettes.

“So, this is not theory.”